How can I construct a matrix by programming in mathematica?

Question

I want to write a matrix in Mathematica by programming. How can I write it?

The matrix is :

$ M= \begin{bmatrix} 0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \end{bmatrix} $

Considering $p$- Number of rows and $2n+1$- Number of columns I wrote the following program which is added. But this code is not working. I can form a matrix by matrix tool option. but it is 1000 entries or more that will a problem.

If only few nonzero elements are to be assigned, SparseArray provides a short and efficient alternative: Normal[SparseArray[{{1,3}->1},{p,2 n +1 }]] — Henrik Schumacher, Oct 30 '18 at 08:36
Essential reading Why I should avoid For loops: https://mathematica.stackexchange.com/questions/134609/why-should-i-avoid-the-for-loop-in-mathematica — High Performance Mark, Oct 30 '18 at 10:19

score 1 · Answer 1 · answered Oct 30 '18 at 08:41

p = 2; n = 5;
mat = ConstantArray[0, {p, 2 n + 1}];
mat[[1, Floor[n/2 + 1]]] = 1;
mat // MatrixForm // TeXForm

$\left( \begin{array}{ccccccccccc} 0 & 0 & 1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ \end{array} \right)$

score 0 · Answer 2 · answered Oct 30 '18 at 10:25

0

How about this

yourMatrix[p_, n_] := SparseArray[{1, Floor[n/2 + 1]} -> 1, {p, 2 n + 1}]

yourMatrix[2, 5] // MatrixForm

answered Oct 30 '18 at 10:25

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How can I construct a matrix by programming in mathematica?

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