logm - square matrix logarithm

Calling Sequence

y=logm(x)

Parameters

• x : square matrix

Description

logm(x) is the matrix logarithm of x. The result is complex if x is not positive or definite positive. If x is a symmetric matrix, then calculation is made by schur form. Otherwise, x is assumed diagonalizable. One has expm(logm(x))=x

Examples

A=[1,2;3,4];
logm(A)
expm(logm(A))
A1=A*A';
logm(A1)
expm(logm(A1))
A1(1,1)=%i;
expm(logm(A1))
 

See Also

expm  log