Functions for Matlab users.
function fliplr (A:numerical) flips a matrix horizontally.
function flipud (A:numerical) flips a matrix vertically.
function rot90 (A:numerical) rotates a matrix counterclockwise
function rot (A:numerical, k:integer=1) rotates a matrix counterclockwise k times 90 degrees
function filter (b:complex vector, a:complex vector, .. x:complex vector, y:complex vector=none, zeros:integer=true) Apply a filter with a and b to start values x and y Computes y[n] recursively using a[1]*y[n]+...+a[m]*y[n-m+1]=b[1]*x[n]+...+b[k]*x[n-k+1] a[1] must not be zero. The start values on the right hand side are either 0 or the first k values of x, depending on the flag zeros (true by default). The start values on the left hand side are either 0 (the default), or the values of the parameter y. The size of a must exceed the size of x by 1. All input vectors must be real or complex row vectors or scalars. See:
filter (Linear Algebra),
fold (Euler Core),
fftfold (Numerical Algorithms)