FreeMat: INV Invert Matrix

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INV Invert Matrix

Section: Transforms/Decompositions

# Usage

Inverts the argument matrix, provided it is square and invertible. The syntax for its use is

       y = inv(x)

Internally, the `inv` function uses the matrix divide operators. For sparse matrices, a sparse matrix solver is used.

# Example

Here we invert some simple matrices

    --> a = randi(zeros(3),5*ones(3))

    a =
     5 3 3
     4 1 3
     5 2 5

    --> b = inv(a)

    b =
        0.0909    0.8182   -0.5455
        0.4545   -0.9091    0.2727
       -0.2727   -0.4545    0.6364

    --> a*b

    ans =
        1.0000    0.0000   -0.0000
        0.0000    1.0000         0
        0.0000    0.0000    1.0000

    --> b*a

    ans =
        1.0000    0.0000         0
        0.0000    1.0000         0
        0.0000   -0.0000    1.0000