IdentityMatrix

IdentityMatrix[n] gives the n×n identity matrix.

IdentityMatrix[{m, n}] gives an m×n identity matrix.

Examples

Create a 3×3 identity matrix:

IdentityMatrix[3]
(* {{1, 0, 0}, {0, 1, 0}, {0, 0, 1}} *)

Rectangular identity matrix:

IdentityMatrix[{2, 3}]
(* {{1, 0, 0}, {0, 1, 0}} *)

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