The Identity function creates a mod m identity Matrix of the specified type and dimensions.

The allowable datatypes are hardware integer (dtype=integer[4]/integer[8] or integer[]), hardware float (dtype=float[8]), or Maple integer (dtype=integer). If specified, order can be C_order or Fortran_order. If not specified, C_order is used.

This command is part of the LinearAlgebra[Modular] package, so it can be used in the form Identity(..) only after executing the command with(LinearAlgebra[Modular]).  However, it can always be used in the form LinearAlgebra[Modular][Identity](..).

$\mathrm{with}\left(\mathrm{LinearAlgebra}\left[\mathrm{Modular}\right]\right)\:$

$\mathrm{A1}≔\mathrm{Identity}\left(31\,20\,\mathrm{integer}\left[\right]\right)$

$\mathrm{A2}≔\mathrm{Identity}\left(31\,20\,\mathrm{float}\left[8\right]\,\mathrm{Fortran\_order}\right)$

$\mathrm{A3}≔\mathrm{Identity}\left(31\,3\,\mathrm{integer}\right)$

$\mathrm{A3}≔\left[\begin{array}{ccc}1& 0& 0\\ 0& 1& 0\\ 0& 0& 1\end{array}\right]$

$\mathrm{A4}≔\mathrm{Identity}\left(31\,5\,\mathrm{float}\left[8\right]\right)$

$\mathrm{A4}≔\left[\begin{array}{ccccc}1.& 0.& 0.& 0.& 0.\\ 0.& 1.& 0.& 0.& 0.\\ 0.& 0.& 1.& 0.& 0.\\ 0.& 0.& 0.& 1.& 0.\\ 0.& 0.& 0.& 0.& 1.\end{array}\right]$