# ApCoCoA-1:Num.EigenValues

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This article is about a function from ApCoCoA-1. |

## Num.EigenValues

Computes the eigenvalues of a matrix.

### Syntax

Num.EigenValues(A:MAT):MAT

### Description

*Please note:* The function(s) explained on this page is/are using the *ApCoCoAServer*. You will have to start the ApCoCoAServer in order to use it/them.

This function computes the approximate complex eigenvalues of the matrix `A`.

@param

*A*A quadratic matrix with rational entries.@return The return value is a matrix with two rows. Each column of this matrix represents one approximate complex eigenvalue of

`A`, i.e. the first entry of a column is the real part and the second entry of the same column is the imaginary part of one complex eigenvalue.

#### Example

Use P::=QQ[x,y,z]; A:=Mat([[1,2,7,18],[2,4,9,12],[23,8,9,10],[7,5,3,2]]); Dec(Num.EigenValues(A),3); -- CoCoAServer: computing Cpu Time = 0.015 ------------------------------- Mat([ ["28.970", "-13.677", "0.353", "0.353"], ["0", "0", "3.051", "-3.051"] ]) -------------------------------

### See also