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I am Oscar and I totally dig that name. He used to be unemployed but now he is a computer operator but his marketing by no means arrives. South Dakota is where I've always been living. To collect cash is what his family and him enjoy.<br><br>Also visit my site ... [http://www.fuguporn.com/user/RScrivene std testing at home]
{{for|the Kronecker product of representations of symmetric groups |Kronecker coefficient}}
In [[mathematics]], the '''Kronecker product''', denoted by ⊗, is an operation on two [[matrix (mathematics)|matrices]] of arbitrary size resulting in a [[block matrix]]. It is a generalization of the [[outer product]] (which is denoted by the same symbol) from vectors to matrices, and gives the matrix of the [[tensor product]] with respect to a standard choice of [[Basis (linear algebra)|basis]]. The Kronecker product should not be confused with the usual [[matrix multiplication]], which is an entirely different operation.
 
The Kronecker product is named after [[Leopold Kronecker]], even though there is little evidence that he was the first to define and use it. Indeed, in the past the Kronecker product was sometimes called the ''Zehfuss matrix,'' after [[Johann Georg Zehfuss]] who described the matrix operation we now know as the Kronecker product in 1858.<ref>{{Citation
| author = G. Zehfuss
| year = 1858
| title = Ueber eine gewisse Determinante
| journal = Zeitschrift für Mathematik und Physik
| volume = 3
| pages = 298&ndash;301
| url = http://resolver.sub.uni-goettingen.de/purl?PPN599415665_0003
| postscript = .
}}</ref>
 
== Definition ==
If '''A''' is an ''m'' × ''n'' matrix and '''B''' is a ''p'' × ''q'' matrix, then the Kronecker product '''A''' ⊗ '''B''' is the ''mp'' × ''nq'' block matrix:
 
:<math>\mathbf{A}\otimes\mathbf{B} = \begin{bmatrix} a_{11} \mathbf{B} & \cdots & a_{1n}\mathbf{B} \\ \vdots & \ddots & \vdots \\ a_{m1} \mathbf{B} & \cdots & a_{mn} \mathbf{B} \end{bmatrix}, </math>
 
more explicitly:
 
:<math>{\mathbf{A}\otimes\mathbf{B}} = \begin{bmatrix}
  a_{11} b_{11} & a_{11} b_{12} & \cdots & a_{11} b_{1q} &
                  \cdots & \cdots & a_{1n} b_{11} & a_{1n} b_{12} & \cdots & a_{1n} b_{1q} \\
  a_{11} b_{21} & a_{11} b_{22} & \cdots & a_{11} b_{2q} &
                  \cdots & \cdots & a_{1n} b_{21} & a_{1n} b_{22} & \cdots & a_{1n} b_{2q} \\
  \vdots & \vdots & \ddots & \vdots & & & \vdots & \vdots & \ddots & \vdots \\
  a_{11} b_{p1} & a_{11} b_{p2} & \cdots & a_{11} b_{pq} &
                  \cdots & \cdots & a_{1n} b_{p1} & a_{1n} b_{p2} & \cdots & a_{1n} b_{pq} \\
  \vdots & \vdots & & \vdots & \ddots & & \vdots & \vdots & & \vdots \\
  \vdots & \vdots & & \vdots & & \ddots & \vdots & \vdots & & \vdots \\
  a_{m1} b_{11} & a_{m1} b_{12} & \cdots & a_{m1} b_{1q} &
                  \cdots & \cdots & a_{mn} b_{11} & a_{mn} b_{12} & \cdots & a_{mn} b_{1q} \\
  a_{m1} b_{21} & a_{m1} b_{22} & \cdots & a_{m1} b_{2q} &
                  \cdots & \cdots & a_{mn} b_{21} & a_{mn} b_{22} & \cdots & a_{mn} b_{2q} \\
  \vdots & \vdots & \ddots & \vdots & & & \vdots & \vdots & \ddots & \vdots \\
  a_{m1} b_{p1} & a_{m1} b_{p2} & \cdots & a_{m1} b_{pq} &
                  \cdots & \cdots & a_{mn} b_{p1} & a_{mn} b_{p2} & \cdots & a_{mn} b_{pq}
\end{bmatrix}. </math>
 
If '''A''' and '''B''' represent [[linear transformations]] '''V'''<sub>1</sub> → '''W'''<sub>1</sub> and '''V'''<sub>2</sub> → '''W'''<sub>2</sub>, respectively, then '''A''' ⊗ '''B''' represents the [[tensor product]] of the two maps, '''V'''<sub>1</sub> ⊗ '''V'''<sub>2</sub> → '''W'''<sub>1</sub> ⊗  '''W'''<sub>2</sub>.
 
=== Examples ===
:<math>
  \begin{bmatrix}
    1 & 2 \\
    3 & 4 \\
  \end{bmatrix}
\otimes
  \begin{bmatrix}
    0 & 5 \\
    6 & 7 \\
  \end{bmatrix}
=
  \begin{bmatrix}
    1\cdot 0 & 1\cdot 5 & 2\cdot 0 & 2\cdot 5 \\
    1\cdot 6 & 1\cdot 7 & 2\cdot 6 & 2\cdot 7 \\
    3\cdot 0 & 3\cdot 5 & 4\cdot 0 & 4\cdot 5 \\
    3\cdot 6 & 3\cdot 7 & 4\cdot 6 & 4\cdot 7 \\
  \end{bmatrix}
 
=
  \begin{bmatrix}
    0 & 5 & 0 & 10 \\
    6 & 7 & 12 & 14 \\
    0 & 15 & 0 & 20 \\
    18 & 21 & 24 & 28
  \end{bmatrix}.
</math>
 
== Properties ==
 
=== Relations to other matrix operations ===
<ol>
<li>'''[[Bilinearity]] and [[associativity]]:'''
 
The Kronecker product is a special case of the [[tensor product]], so it is [[bilinear operator|bilinear]] and [[associativity|associative]]:
:<math> \mathbf{A} \otimes (\mathbf{B}+\mathbf{C}) = \mathbf{A} \otimes \mathbf{B} + \mathbf{A} \otimes \mathbf{C}, </math>
:<math> (\mathbf{A}+\mathbf{B})\otimes \mathbf{C} = \mathbf{A} \otimes \mathbf{C} + \mathbf{B} \otimes \mathbf{C}, </math>
:<math> (k\mathbf{A}) \otimes \mathbf{B} = \mathbf{A} \otimes (k\mathbf{B}) = k(\mathbf{A} \otimes \mathbf{B}), </math>
:<math> (\mathbf{A} \otimes \mathbf{B}) \otimes \mathbf{C} = \mathbf{A} \otimes (\mathbf{B} \otimes \mathbf{C}), </math>
where '''A''', '''B''' and '''C''' are matrices and ''k'' is a scalar.
</li>
<li>'''Non-[[commutative operation|commutative]]:'''
 
In general '''A''' ⊗ '''B''' and '''B''' ⊗ '''A''' are different matrices. However, '''A''' ⊗ '''B''' and '''B''' ⊗ '''A''' are permutation equivalent, meaning that there exist [[permutation matrix|permutation matrices]] '''P''' and '''Q''' such that
:<math> \mathbf{A} \otimes \mathbf{B} = \mathbf{P} \, (\mathbf{B} \otimes \mathbf{A}) \, \mathbf{Q}. </math>
If '''A''' and '''B''' are square matrices, then '''A''' ⊗ '''B''' and '''B''' ⊗ '''A''' are even permutation [[Similar matrix|similar]], meaning that we can take '''P''' = '''Q'''<sup>T</sup>.
</li>
<li>'''The mixed-product property and the inverse of a Kronecker product:'''
 
If '''A''', '''B''', '''C''' and '''D''' are matrices of such size that one can form the matrix products '''AC''' and '''BD''', then
:<math> (\mathbf{A} \otimes \mathbf{B})(\mathbf{C} \otimes \mathbf{D}) = \mathbf{AC} \otimes \mathbf{BD}. </math>
This is called the ''mixed-product property,'' because it mixes the ordinary matrix product and the Kronecker product. It follows that '''A''' ⊗ '''B''' is [[invertible matrix|invertible]] [[if and only if]] '''A''' and '''B''' are invertible, in which case the inverse is given by
:<math> (\mathbf{A} \otimes \mathbf{B})^{-1} = \mathbf{A}^{-1} \otimes \mathbf{B}^{-1}. </math>
</li>
<li>'''[[Transpose]]:'''
 
The transposition and [[conjugate transpose|conjugate transposition]] are distributive over the Kronecker product:
:<math>(\mathbf{A}\otimes \mathbf{B})^T = \mathbf{A}^T \otimes \mathbf{B}^T</math> and <math>(\mathbf{A}\otimes \mathbf{B})^* = \mathbf{A}^* \otimes \mathbf{B}^*.</math>
</li>
<li>'''[[Determinant]]:'''
 
Let '''A''' be an ''n'' × ''n'' matrix and let '''B''' be a ''p'' × ''p'' matrix. Then
:<math> |\mathbf{A}\otimes \mathbf{B}| = |\mathbf{A}|^p |\mathbf{B}|^n.</math>
The exponent in |'''A'''| is the order of '''B''' and the exponent in |'''B'''| is the order of '''A'''.
</li>
<li>'''Kronecker sum and [[Matrix exponential|exponentiation]] {{Anchor|Kronecker sum}}'''
 
If '''A''' is ''n'' × ''n'', '''B''' is ''m'' × ''m'' and '''I'''<sub>''k''</sub> denotes the ''k'' × ''k'' [[identity matrix]] then we can define what is sometimes called the '''Kronecker sum''', &oplus;, by
:<math> \mathbf{A} \oplus \mathbf{B} = \mathbf{A} \otimes \mathbf{I}_m + \mathbf{I}_n \otimes \mathbf{B}. </math>
Note that this is ''different'' from the [[Matrix addition#Direct sum|''direct sum'']] of two matrices. This operation is related to the tensor product on [[Lie algebra]]s.
 
We have the following formula for the [[matrix exponential]] which is useful in the numerical evaluation of certain [[continuous-time Markov process]]es {{Citation needed|date=January 2008}},
:<math> e^{\mathbf{A} \oplus \mathbf{B}} = e^\mathbf{A} \otimes e^\mathbf{B}. </math>
 
Kronecker sums appear naturally in [[physics]] when considering ensembles of non-interacting [[Physical system|systems]]. Let ''H<sup>i</sup>'' be the Hamiltonian of the ''i''-th such system. Then the total Hamiltonian of the ensemble is  
:<math>H_{\mathrm{Tot}}=\bigoplus_{i}H^{i}</math>.
</li>
</ol>
 
=== Abstract properties ===
<ol>
<li>'''[[Spectrum (functional analysis)|Spectrum]]:'''
 
Suppose that '''A''' and '''B''' are square matrices of size ''n'' and ''m'' respectively. Let λ<sub>1</sub>, ..., λ<sub>''n''</sub> be the [[eigenvalue]]s of '''A''' and μ<sub>1</sub>, ..., μ<sub>''m''</sub> be those of '''B''' (listed according to [[Multiplicity (mathematics)|multiplicity]]). Then the [[eigenvalues]] of '''A''' ⊗ '''B''' are
:<math> \lambda_i \mu_j, \qquad i=1,\ldots,n ,\, j=1,\ldots,m. </math>
It follows that the [[trace (matrix)|trace]] and [[determinant]] of a Kronecker product are given by
:<math> \mathrm{tr}(\mathbf{A} \otimes \mathbf{B}) = \mathrm{tr} \mathbf{A} \, \mathrm{tr} \mathbf{B} \quad\mbox{and}\quad \det(\mathbf{A} \otimes \mathbf{B}) = (\det \mathbf{A})^m (\det \mathbf{B})^n. </math>
</li>
<li>'''[[singular value decomposition|Singular values]]:'''
 
If '''A''' and '''B''' are rectangular matrices, then one can consider their [[singular value decomposition|singular values]]. Suppose that '''A''' has ''r''<sub>'''A'''</sub> nonzero singular values, namely
:<math> \sigma_{\mathbf{A},i}, \qquad i = 1, \ldots, r_\mathbf{A}. </math>
Similarly, denote the nonzero singular values of '''B''' by
:<math> \sigma_{\mathbf{B},i}, \qquad i = 1, \ldots, r_\mathbf{B}. </math>
Then the Kronecker product '''A''' ⊗ '''B''' has ''r''<sub>'''A'''</sub>''r''<sub>'''B'''</sub> nonzero singular values, namely
:<math> \sigma_{\mathbf{A},i} \sigma_{\mathbf{B},j}, \qquad i=1,\ldots,r_\mathbf{A} ,\, j=1,\ldots,r_\mathbf{B}. </math>
Since the [[rank of a matrix]] equals the number of nonzero singular values, we find that
:<math> \mathrm{rank}(\mathbf{A} \otimes \mathbf{B}) = \mathrm{rank} \mathbf{A} \, \mathrm{rank} \mathbf{B}. </math>
</li>
<li>'''Relation to the abstract [[tensor product]]:'''
 
The Kronecker product of matrices corresponds to the abstract tensor product of linear maps. Specifically, if the vector spaces ''V'', ''W'', ''X'', and ''Y'' have bases {v<sub>1</sub>, ..., v<sub>m</sub>}, {w<sub>1</sub>, ..., w<sub>n</sub>}, {x<sub>1</sub>, ..., x<sub>d</sub>}, and {y<sub>1</sub>, ..., y<sub>e</sub>}, respectively, and if the matrices ''A'' and ''B'' represent the linear transformations ''S'' : ''V'' → ''X'' and ''T'' : ''W'' → ''Y'', respectively in the appropriate bases, then the matrix ''A'' ⊗ ''B'' represents the tensor product of the two maps, ''S'' ⊗ ''T'' : ''V'' ⊗ ''W'' → ''X'' ⊗ ''Y'' with respect to the basis {v<sub>1</sub> ⊗ w<sub>1</sub>, v<sub>1</sub> ⊗ w<sub>2</sub>, ..., v<sub>2</sub> ⊗ w<sub>1</sub>, ..., v<sub>m</sub> ⊗ w<sub>n</sub>} of ''V'' ⊗ ''W'' and the similarly defined basis of ''X'' ⊗ ''Y'' with the property that ''A'' ⊗ ''B''(v<sub>i</sub> ⊗ w<sub>j</sub>) = (''A''v<sub>i</sub>)⊗(''B''w<sub>j</sub>), where i and j are integers in the proper range.<ref>Pages 401&ndash;402 of {{Citation
| last=Dummit
| first=David S.
| last2=Foote
| first2=Richard M.
| title=Abstract Algebra
| edition=2
| year=1999
| publisher=John Wiley and Sons, Inc.
| place=New York
| isbn=0-471-36857-1
}}</ref>
 
When ''V'' and ''W'' are [[Lie algebra]]s, and ''S'' : ''V'' → ''V'' and ''T'' : ''W'' → ''W'' are [[Lie algebra homomorphism]]s, the Kronecker sum of ''A'' and ''B'' represents the induced Lie algebra homomorphisms ''V'' ⊗ ''W'' → ''V'' ⊗ ''W''.
</li>
<li>'''Relation to [[matrix multiplication|product]]s of [[graph theory|graph]]s:'''
 
The Kronecker product of the [[adjacency matrix|adjacency matrices]] of two [[graph (mathematics)|graphs]] is the adjacency matrix of the [[tensor product of graphs|tensor product graph]]. The [[Kronecker product#Kronecker sum and exponentiation|Kronecker sum]] of the adjacency matrices of two [[graph (mathematics)|graphs]] is the adjacency matrix of the [[cartesian product of graphs|Cartesian product graph]]. See,<ref name="TAOCP0a">D. E. Knuth: ''
[http://www-cs-faculty.stanford.edu/~knuth/fasc0a.ps.gz "Pre-Fascicle 0a: Introduction to Combinatorial Algorithms"], zeroth printing (revision 2), to appear as part of D.E. Knuth: ''The Art of Computer Programming Vol. 4A''</ref> answer to Exercise 96.
</li>
</ol>
 
== Matrix equations ==
The Kronecker product can be used to get a convenient representation for some matrix equations. Consider for instance the equation '''AXB''' = '''C''', where '''A''', '''B''' and '''C''' are given matrices and the matrix '''X''' is the unknown. We can rewrite this equation as
:<math> (\mathbf{B}^\top \otimes \mathbf{A}) \, \operatorname{vec}(\mathbf{X}) = \operatorname{vec}(\mathbf{AXB}) = \operatorname{vec}(\mathbf{C}). </math>
 
Here, vec('''X''') denotes the [[Vectorization (mathematics)|vectorization]] of the matrix '''X''' formed by stacking the columns of '''X''' into a single [[column vector]].
It now follows from the properties of the Kronecker product that the equation '''AXB''' = '''C''' has a unique solution if and only if '''A''' and '''B''' are nonsingular {{harv|Horn|Johnson|1991|loc=Lemma 4.3.1}}.
 
If '''X''' is row-ordered into the column vector '''x''' then '''AXB''' can be also be written as {{harv|Jain|1989|loc=2.8 Block Matrices and Kronecker Products}} ('''A''' ⊗ '''B'''<sup>T</sup>)'''x'''.
 
== Related matrix operations {{Anchor|Tracy-Singh and Khatri-Rao products}} ==
Two related matrix operations are the '''Tracy-Singh''' and '''Khatri-Rao products''' which operate on [[Block matrix|partitioned matrices]].  Let the ''m'' × ''n'' matrix '''A''' be partitioned into the ''m<sub>i</sub>'' × ''n<sub>j</sub>'' blocks '''A'''<sub>''ij''</sub> and ''p'' × ''q'' matrix '''B''' into the ''p<sub>k</sub>'' × ''q<sub>{{ell}}</sub>'' blocks '''B'''<sub>''kl''</sub> with of course Σ''<sub>i</sub> m<sub>i</sub>'' = ''m'', Σ''<sub>j</sub> n<sub>j</sub>'' = ''n'', Σ''<sub>k</sub> p<sub>k</sub>'' = ''p'' and Σ''<sub>{{ell}}</sub> q<sub>{{ell}}</sub>'' = ''q''.
 
===Tracy-Singh product===
The Tracy-Singh product<ref>Tracy, DS, Singh RP. 1972. A new matrix product and its applications in matrix differentiation. Statistica Neerlandica 26: 143&ndash;157.</ref><ref>Liu S. 1999. Matrix results on the Khatri-Rao and Tracy-Singh products. Linear Algebra and its Applications 289: 267&ndash;277. ([http://www.sciencedirect.com/science?_ob=MImg&_imagekey=B6V0R-3YVMNR9-R-1&_cdi=5653&_user=877992&_orig=na&_coverDate=03%2F01%2F1999&_sk=997109998&view=c&wchp=dGLbVlb-zSkWb&md5=21c8c66f17da8d1bab45304a29cc96ac&ie=/sdarticle.pdf pdf])</ref>
is defined as
 
:<math> \mathbf{A} \circ \mathbf{B} = (\mathbf{A}_{ij}\circ \mathbf{B})_{ij} = ((\mathbf{A}_{ij} \otimes \mathbf{B}_{kl})_{kl})_{ij}</math>
 
which means that the (''ij'')-th subblock of the ''mp'' × ''nq'' product '''A''' ○ '''B''' is the ''m<sub>i</sub> p'' × ''n<sub>j</sub> q'' matrix '''A'''<sub>''ij''</sub> ○ '''B''', of which the (''k{{ell}}'')-th subblock equals the ''m<sub>i</sub> p<sub>k</sub>'' × ''n<sub>j</sub> q<sub>{{ell}}</sub>'' matrix '''A'''<sub>''ij''</sub> ⊗ '''B'''<sub>''k{{ell}}''</sub>. Essentially the Tracy-Singh product is the pairwise Kronecker product for each pair of partitions in the two matrices.
 
For example, if '''A''' and '''B''' both are 2 × 2 partitioned matrices e.g.:
:<math> \mathbf{A} =
\left[
\begin{array} {c | c}
\mathbf{A}_{11} & \mathbf{A}_{12} \\
\hline
\mathbf{A}_{21} & \mathbf{A}_{22}
\end{array}
\right]
=
\left[
\begin{array} {c c | c}
1 & 2 & 3 \\
4 & 5 & 6 \\
\hline
7 & 8 & 9
\end{array}
\right]
,\quad
\mathbf{B} =
\left[
\begin{array} {c | c}
\mathbf{B}_{11} & \mathbf{B}_{12} \\
\hline
\mathbf{B}_{21} & \mathbf{B}_{22}
\end{array}
\right]
=
\left[
\begin{array} {c | c c}
1 & 4 & 7 \\
\hline
2 & 5 & 8 \\
3 & 6 & 9
\end{array}
\right]
,
</math>
we get:
:<math>
\mathbf{A} \circ \mathbf{B} =
\left[
\begin{array} {c | c}
\mathbf{A}_{11} \circ \mathbf{B} & \mathbf{A}_{12} \circ \mathbf{B} \\
\hline
\mathbf{A}_{21} \circ \mathbf{B} & \mathbf{A}_{22} \circ \mathbf{B}
\end{array}
\right]
=
\left[
\begin{array} {c | c | c | c }
\mathbf{A}_{11} \otimes \mathbf{B}_{11} & \mathbf{A}_{11} \otimes \mathbf{B}_{12} & \mathbf{A}_{12} \otimes \mathbf{B}_{11} & \mathbf{A}_{12} \otimes \mathbf{B}_{12} \\
\hline
\mathbf{A}_{11} \otimes \mathbf{B}_{21} & \mathbf{A}_{11} \otimes \mathbf{B}_{22} & \mathbf{A}_{12} \otimes \mathbf{B}_{21} & \mathbf{A}_{12} \otimes \mathbf{B}_{22} \\
\hline
\mathbf{A}_{21} \otimes \mathbf{B}_{11} & \mathbf{A}_{21} \otimes \mathbf{B}_{12} & \mathbf{A}_{22} \otimes \mathbf{B}_{11} & \mathbf{A}_{22} \otimes \mathbf{B}_{12} \\
\hline
\mathbf{A}_{21} \otimes \mathbf{B}_{21} & \mathbf{A}_{21} \otimes \mathbf{B}_{22} & \mathbf{A}_{22} \otimes \mathbf{B}_{21} & \mathbf{A}_{22} \otimes \mathbf{B}_{22}
\end{array}
\right]
</math>
:<math>
=
\left[
\begin{array} {c c | c c c c | c | c c}
1 & 2 & 4 & 7 & 8 & 14 & 3 & 12 & 21 \\
4 & 5 & 16 & 28 & 20 & 35 & 6 & 24 & 42 \\
\hline
2 & 4 & 5 & 8 & 10 & 16 & 6 & 15 & 24 \\
3 & 6 & 6 & 9 & 12 & 18 & 9 & 18 & 27 \\
8 & 10 & 20 & 32 & 25 & 40 & 12 & 30 & 48 \\
12 & 15 & 24 & 36 & 30 & 45 & 18 & 36 & 54 \\
\hline
7 & 8 & 28 & 49 & 32 & 56 & 9 & 36 & 63 \\
\hline
14 & 16 & 35 & 56 & 40 & 64 & 18 & 45 & 72 \\
21 & 24 & 42 & 63 & 48 & 72 & 27 & 54 & 81
\end{array}
\right].
</math>
 
===Khatri-Rao product===
The Khatri-Rao product<ref>{{Citation
| author = Khatri C. G., [[C. R. Rao]]
| year = 1968
| title = Solutions to some functional equations and their applications to characterization of probability distributions
| journal = [[Sankhya (journal)|Sankhya]]
| volume = 30
| pages = 167&ndash;180
| url = http://sankhya.isical.ac.in/search/30a2/30a2019.html
| postscript = .
}}</ref><ref>{{Citation
| author = Zhang X, Yang Z, Cao C.
| year = 2002
| title = Inequalities involving Khatri-Rao products of positive semi-definite matrices
| journal = Applied Mathematics E-notes
| volume = 2
| pages = 117&ndash;124
| postscript = .
}}</ref>
is defined as
:<math> \mathbf{A} \ast \mathbf{B} = (\mathbf{A}_{ij}\otimes \mathbf{B}_{ij})_{ij}</math>
in which the ''ij''-th block is the ''m<sub>i</sub>p<sub>i</sub>'' × ''n<sub>j</sub>q<sub>j</sub>'' sized Kronecker product of the corresponding blocks of '''A''' and '''B''', assuming the number of row and column partitions of both matrices is equal.  The size of the product is then (Σ''<sub>i</sub> m<sub>i</sub>p<sub>i</sub>'') × (Σ''<sub>j</sub> n<sub>j</sub>q<sub>j</sub>'').  Proceeding with the same matrices as the previous example we obtain:
:<math>
\mathbf{A} \ast \mathbf{B} =
\left[
\begin{array} {c | c}
\mathbf{A}_{11} \otimes \mathbf{B}_{11} & \mathbf{A}_{12} \otimes \mathbf{B}_{12} \\
\hline
\mathbf{A}_{21} \otimes \mathbf{B}_{21} & \mathbf{A}_{22} \otimes \mathbf{B}_{22}
\end{array}
\right]
=
\left[
\begin{array} {c c | c c}
1 & 2 & 12 & 21 \\
4 & 5 & 24 & 42 \\
\hline
14 & 16 & 45 & 72 \\
21 & 24 & 54 & 81
\end{array}
\right].
</math>
 
This is a submatrix of the Tracy-Singh product of the two matrices (each partition in this example is a partition in a corner of the Tracy-Singh product).
 
<!-- comment: the following definition is the same as the above except that it uses implicit partitions instead of explicit partitions... is there really need for this second example? -->
 
A column-wise Kronecker product of two matrices may also be called the Khatri-Rao product. This product assumes the partitions of the matrices are their columns.  In this case ''m''<sub>1</sub> = ''m'', ''p''<sub>1</sub> = ''p'', ''n'' = ''q'' and for each ''j'': ''n<sub>j</sub>'' = ''p<sub>j</sub>'' = 1.  The resulting product is a ''mp'' × ''n'' matrix of which each column is the Kronecker product of the corresponding columns of ''A'' and ''B''.  Using the matrices from the previous examples with the columns partitioned:
:<math>
\mathbf{C} =
\left[
\begin{array} { c | c | c}
\mathbf{C}_1 & \mathbf{C}_2 & \mathbf{C}_3
\end{array}
\right]
=
\left[
\begin{array} {c | c | c}
1 & 2 & 3 \\
4 & 5 & 6 \\
7 & 8 & 9
\end{array}
\right]
,\quad
\mathbf{D} =
\left[
\begin{array} { c | c | c }
\mathbf{D}_1 & \mathbf{D}_2 & \mathbf{D}_3
\end{array}
\right]
=
\left[
\begin{array} { c | c | c }
1 & 4 & 7 \\
2 & 5 & 8 \\
3 & 6 & 9
\end{array}
\right]
,
</math>
so that:
:<math>
\mathbf{C} \ast \mathbf{D}
=
\left[
\begin{array} { c | c | c }
\mathbf{C}_1 \otimes \mathbf{D}_1 & \mathbf{C}_2 \otimes \mathbf{D}_2 & \mathbf{C}_3 \otimes \mathbf{D}_3
\end{array}
\right]
=
\left[
\begin{array} { c | c | c }
1 & 8 & 21 \\
2 & 10 & 24 \\
3 & 12 & 27 \\
4 & 20 & 42 \\
8 & 25 & 48 \\
12 & 30 & 54 \\
7 & 32 & 63 \\
14 & 40 & 72 \\
21 & 48 & 81
\end{array}
\right].
</math>
 
==See also==
* [[Generalized linear array model]]
* [[Matrix product]]
 
== Notes ==
{{Reflist}}
 
== References ==
* {{citation | first1=Roger A. | last1=Horn | first2=Charles R. | last2=Johnson | year=1991 | title=Topics in Matrix Analysis | publisher=Cambridge University Press | isbn=0-521-46713-6 }}.
*{{citation | first1=Anil K. | last1=Jain | year = 1989 | title=Fundamentals of Digital Image Processing | publisher= Prentice Hall | isbn=0-13-336165-9}}.
* {{citation | first1=Willi-Hans | last=Steeb | year=1997 | title=Matrix Calculus and Kronecker Product with Applications and C++ Programs | publisher=World Scientific Publishing | isbn=981-02-3241-1 }}
* {{citation | first1=Willi-Hans | last=Steeb | year=2006 | title=Problems and Solutions in Introductory and Advanced Matrix Calculus | publisher=World Scientific Publishing | isbn=981-256-916-2 }}
 
== External links ==
* {{springer|title=Tensor product|id=p/t092410}}
* {{planetmath reference|id=4163|title=Kronecker product}}
* [http://mathworld.wolfram.com/KroneckerProduct.html MathWorld Kronecker Product]
* [http://issc.uj.ac.za/downloads/problems/newkronecker.pdf New Kronecker product problems]
* [http://jeff560.tripod.com/k.html Earliest Uses: The entry on The Kronecker, Zehfuss or Direct Product of matrices has historical information.]
* [[:sourceforge:projects/kronecker/|Generic C++ and Fortran 90 codes for calculating Kronecker products of two matrices.]]
 
{{DEFAULTSORT:Kronecker Product}}
[[Category:Matrix theory]]

Latest revision as of 22:13, 11 March 2013

28 year-old Painting Investments Worker Truman from Regina, usually spends time with pastimes for instance interior design, property developers in new launch ec Singapore and writing. Last month just traveled to City of the Renaissance. In mathematics, the Kronecker product, denoted by ⊗, is an operation on two matrices of arbitrary size resulting in a block matrix. It is a generalization of the outer product (which is denoted by the same symbol) from vectors to matrices, and gives the matrix of the tensor product with respect to a standard choice of basis. The Kronecker product should not be confused with the usual matrix multiplication, which is an entirely different operation.

The Kronecker product is named after Leopold Kronecker, even though there is little evidence that he was the first to define and use it. Indeed, in the past the Kronecker product was sometimes called the Zehfuss matrix, after Johann Georg Zehfuss who described the matrix operation we now know as the Kronecker product in 1858.[1]

Definition

If A is an m × n matrix and B is a p × q matrix, then the Kronecker product AB is the mp × nq block matrix:

more explicitly:

If A and B represent linear transformations V1W1 and V2W2, respectively, then AB represents the tensor product of the two maps, V1V2W1W2.

Examples

Properties

Relations to other matrix operations

  1. Bilinearity and associativity: The Kronecker product is a special case of the tensor product, so it is bilinear and associative:
    where A, B and C are matrices and k is a scalar.
  2. Non-commutative: In general AB and BA are different matrices. However, AB and BA are permutation equivalent, meaning that there exist permutation matrices P and Q such that
    If A and B are square matrices, then AB and BA are even permutation similar, meaning that we can take P = QT.
  3. The mixed-product property and the inverse of a Kronecker product: If A, B, C and D are matrices of such size that one can form the matrix products AC and BD, then
    This is called the mixed-product property, because it mixes the ordinary matrix product and the Kronecker product. It follows that AB is invertible if and only if A and B are invertible, in which case the inverse is given by
  4. Transpose: The transposition and conjugate transposition are distributive over the Kronecker product:
    and
  5. Determinant: Let A be an n × n matrix and let B be a p × p matrix. Then
    The exponent in |A| is the order of B and the exponent in |B| is the order of A.
  6. Kronecker sum and exponentiation <Kronecker sum>...</Kronecker sum> If A is n × n, B is m × m and Ik denotes the k × k identity matrix then we can define what is sometimes called the Kronecker sum, ⊕, by
    Note that this is different from the direct sum of two matrices. This operation is related to the tensor product on Lie algebras. We have the following formula for the matrix exponential which is useful in the numerical evaluation of certain continuous-time Markov processes Potter or Ceramic Artist Truman Bedell from Rexton, has interests which include ceramics, best property developers in singapore developers in singapore and scrabble. Was especially enthused after visiting Alejandro de Humboldt National Park.,
    Kronecker sums appear naturally in physics when considering ensembles of non-interacting systems. Let Hi be the Hamiltonian of the i-th such system. Then the total Hamiltonian of the ensemble is
    .

Abstract properties

  1. Spectrum: Suppose that A and B are square matrices of size n and m respectively. Let λ1, ..., λn be the eigenvalues of A and μ1, ..., μm be those of B (listed according to multiplicity). Then the eigenvalues of AB are
    It follows that the trace and determinant of a Kronecker product are given by
  2. Singular values: If A and B are rectangular matrices, then one can consider their singular values. Suppose that A has rA nonzero singular values, namely
    Similarly, denote the nonzero singular values of B by
    Then the Kronecker product AB has rArB nonzero singular values, namely
    Since the rank of a matrix equals the number of nonzero singular values, we find that
  3. Relation to the abstract tensor product: The Kronecker product of matrices corresponds to the abstract tensor product of linear maps. Specifically, if the vector spaces V, W, X, and Y have bases {v1, ..., vm}, {w1, ..., wn}, {x1, ..., xd}, and {y1, ..., ye}, respectively, and if the matrices A and B represent the linear transformations S : VX and T : WY, respectively in the appropriate bases, then the matrix AB represents the tensor product of the two maps, ST : VWXY with respect to the basis {v1 ⊗ w1, v1 ⊗ w2, ..., v2 ⊗ w1, ..., vm ⊗ wn} of VW and the similarly defined basis of XY with the property that AB(vi ⊗ wj) = (Avi)⊗(Bwj), where i and j are integers in the proper range.[2] When V and W are Lie algebras, and S : VV and T : WW are Lie algebra homomorphisms, the Kronecker sum of A and B represents the induced Lie algebra homomorphisms VWVW.
  4. Relation to products of graphs: The Kronecker product of the adjacency matrices of two graphs is the adjacency matrix of the tensor product graph. The Kronecker sum of the adjacency matrices of two graphs is the adjacency matrix of the Cartesian product graph. See,[3] answer to Exercise 96.

Matrix equations

The Kronecker product can be used to get a convenient representation for some matrix equations. Consider for instance the equation AXB = C, where A, B and C are given matrices and the matrix X is the unknown. We can rewrite this equation as

Here, vec(X) denotes the vectorization of the matrix X formed by stacking the columns of X into a single column vector. It now follows from the properties of the Kronecker product that the equation AXB = C has a unique solution if and only if A and B are nonsingular Template:Harv.

If X is row-ordered into the column vector x then AXB can be also be written as Template:Harv (ABT)x.

Related matrix operations <Tracy-Singh and Khatri-Rao products>...</Tracy-Singh and Khatri-Rao products>

Two related matrix operations are the Tracy-Singh and Khatri-Rao products which operate on partitioned matrices. Let the m × n matrix A be partitioned into the mi × nj blocks Aij and p × q matrix B into the pk × qTemplate:Ell blocks Bkl with of course Σi mi = m, Σj nj = n, Σk pk = p and ΣTemplate:Ell qTemplate:Ell = q.

Tracy-Singh product

The Tracy-Singh product[4][5] is defined as

which means that the (ij)-th subblock of the mp × nq product AB is the mi p × nj q matrix AijB, of which the (kTemplate:Ell)-th subblock equals the mi pk × nj qTemplate:Ell matrix AijBkTemplate:Ell. Essentially the Tracy-Singh product is the pairwise Kronecker product for each pair of partitions in the two matrices.

For example, if A and B both are 2 × 2 partitioned matrices e.g.:

we get:

Khatri-Rao product

The Khatri-Rao product[6][7] is defined as

in which the ij-th block is the mipi × njqj sized Kronecker product of the corresponding blocks of A and B, assuming the number of row and column partitions of both matrices is equal. The size of the product is then (Σi mipi) × (Σj njqj). Proceeding with the same matrices as the previous example we obtain:

This is a submatrix of the Tracy-Singh product of the two matrices (each partition in this example is a partition in a corner of the Tracy-Singh product).


A column-wise Kronecker product of two matrices may also be called the Khatri-Rao product. This product assumes the partitions of the matrices are their columns. In this case m1 = m, p1 = p, n = q and for each j: nj = pj = 1. The resulting product is a mp × n matrix of which each column is the Kronecker product of the corresponding columns of A and B. Using the matrices from the previous examples with the columns partitioned:

so that:

See also

Notes

43 year old Petroleum Engineer Harry from Deep River, usually spends time with hobbies and interests like renting movies, property developers in singapore new condominium and vehicle racing. Constantly enjoys going to destinations like Camino Real de Tierra Adentro.

References

  • Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.

    Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.

    In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.

    Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region

    Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.

    15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.

    To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010.
  • Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.

    Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.

    In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.

    Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region

    Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.

    15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.

    To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010.
  • Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.

    Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.

    In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.

    Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region

    Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.

    15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.

    To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010
  • Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.

    Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.

    In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.

    Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region

    Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.

    15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.

    To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010

External links

  1. Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.

    Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.

    In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.

    Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region

    Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.

    15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.

    To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010
  2. Pages 401–402 of Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.

    Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.

    In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.

    Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region

    Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.

    15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.

    To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010
  3. D. E. Knuth: "Pre-Fascicle 0a: Introduction to Combinatorial Algorithms", zeroth printing (revision 2), to appear as part of D.E. Knuth: The Art of Computer Programming Vol. 4A
  4. Tracy, DS, Singh RP. 1972. A new matrix product and its applications in matrix differentiation. Statistica Neerlandica 26: 143–157.
  5. Liu S. 1999. Matrix results on the Khatri-Rao and Tracy-Singh products. Linear Algebra and its Applications 289: 267–277. (pdf)
  6. Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.

    Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.

    In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.

    Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region

    Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.

    15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.

    To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010
  7. Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.

    Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.

    In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.

    Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region

    Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.

    15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.

    To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010