octave:1> help inv `inv' is a function from the file C:\Octave\Octave3.4.3_gcc4.5.2\Octave3.4.3_gcc 4.5.2\lib\octave\3.4.3\oct\i686-pc-mingw32\inv.oct -- Loadable Function: X = inv (A) -- Loadable Function: [X, RCOND] = inv (A) Compute the inverse of the square matrix A. Return an estimate of the reciprocal condition number if requested, otherwise warn of ill-conditioned matrix if the reciprocal condition number is In general it is best to avoid calculating the inverse directly. For example, it is both faster and more `Y = A \of equations (A*x = b) with If called with a sparse matrix requiring in general X will be a full of asignificantly more storage. Avoid forming the inverse See also: ldivide, rdivideble. Additional help for built-in functions and operators is available in the on-line version of the manual. Use the command `doc ' to search the manual index. Help and information about Octave is also available on the WWW at http://www.octave.org and via the help@octave.org mailing list.