Re: [SciPy-user] assign to diagonal values?

On 30-Jan-08, at 10:08 PM, Alan G Isaac wrote:

#diagrv: insert v as diagonal of matrix x (2D only!) def diagrv(x,v,copy=True): assert(len(x.shape)==2), "For 2-d arrays only." x = numpy.matrix( x, copy=copy ) stride = 1 + x.shape[1] x.flat[ slice(0,None,stride) ] = v return x

Ooh that is clever. This should really go on the Cookbook page. Perhaps more generally, for in place modification: def setdiag(m, d): assert(len(x.shape) == 2) stride = 1 + x.shape[1] m.flat[slice(0,None,stride)] = d Regards, David