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1,999 bytes added ,  07:39, 26 October 2015
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<div style="font-size:30px">'''SHIFT'''</div><br/>
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<div style="font-size:30px">'''MATRIX("SHIFT",order)'''</div><br/>
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*<math>order</math> is the size of the Shift matrix.
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==Description==
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*This function returns shift matrix of order 3.
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*A shift matrix is a binary matrix with ones only on the superdiagonal or subdiagonal, and zeroes elsewhere.
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*A shift matrix U with ones on the superdiagonal is an upper shift matrix.
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*The alternative subdiagonal matrix L is unsurprisingly known as a lower shift matrix.
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*Let Z is a shift matrix , then <math>ZA, Z^TA, AZ, AZ^T, ZAZ^T</math> are equal to the matrix A shifted one position down, up left, right, and down along the main diagonal respectively.
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*The alternative subdiagonal matrix L is unsurprisingly known as a lower shift matrix.
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*The <math>(i,j)^{th}</math> component of U and L are:
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<math>U_{ij} = \delta_{i+1,j},  \quad L_{ij} = \delta_{i,j+1}</math>.
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where <math>\delta_{ij}</math> is the Kronecker delta symbol.
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*For example, the 5×5 shift matrices are
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<math>U_5=\begin{pmatrix}
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0 & 1 & 0 & 0 & 0 \\
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0 & 0 & 1 & 0 & 0 \\
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0 & 0 & 0 & 1 & 0 \\
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0 & 0 & 0 & 0 & 1 \\
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0 & 0 & 0 & 0 & 0
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\end{pmatrix}</math>
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<math>L_5 = \begin{pmatrix}
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0 & 0 & 0 & 0 & 0  \\
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1 & 0 & 0 & 0 & 0 \\
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0 & 1 & 0 & 0 & 0 \\
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0 & 0 & 1 & 0 & 0 \\
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0 & 0 & 0 & 0 & 0
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\end{pmatrix}</math>
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*All shift matrices are nilpotent; an n by n shift matrix S becomes the null matrix when raised to the power of its dimension n.
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==Examples==
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*1.MATRIX("shift") = 0
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*2.MATRIX("shift",3)
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{| class="wikitable"
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|-
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| 0 || 1 || 0
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|-
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| 0 || 0 || 1
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|-
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| 0 || 0 || 0
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|}
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*3.MATRIX("shift",7)
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{| class="wikitable"
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|-
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| 0 || 1 || 0 || 0 || 0 || 0 || 0
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|-
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| 0 || 0 || 1 || 0 || 0 || 0 || 0
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|-
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| 0 || 0 || 0 || 1 || 0 || 0 || 0
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|-
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| 0 || 0 || 0 || 0 || 1 || 0 || 0
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|-
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| 0 || 0 || 0 || 0 || 0 || 1 || 0
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|-
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| 0 || 0 || 0 || 0 || 0 || 0 || 1
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|-
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| 0 || 0 || 0 || 0 || 0 || 0 || 0
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|}
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==See Also==
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*[[Manuals/calci/SIGNATURE| SIGNATURE]]
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*[[Manuals/calci/CONFERENCE| CONFERENCE]]
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*[[Manuals/calci/TRIANGULAR| TRIANGULAR]]
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==References==
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*[http://en.wikipedia.org/wiki/Shift_matrix Shift Matrix]
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