On Thu, 8 Sep 2011, Allin Cottrell wrote: > [...] The operation Artur mentions, namely assigning a > scalar value to a single element of a matrix, is a special > case of assignment to a sub-matrix, which has the general > form: > > M[r1:r2,c1:c2] = <expression> > > where the r's and c's are expressions that evaluate to row > and column indices. This demands a lot more parsing effort > than assigning a scalar value to a place in a series (where > the only valid specifier on the left is a single observation > number). > > We could maybe write a dedicated, faster function for the > special case, but even then we first have to figure out that > we're actually in that special case.
In fact quite a nice speed-up was available here. Things should look better in current CVS. Allin
