vector division

[asp]

hello,

i'm looking for a lapack function equivalent to MATLAB's "./" operation which e.g. for two vectors x and y of the same dimensions does element wise division, i.e. it returns a vector of the same dimentions as x and y whose elements are x_i/y_i.
is there anything similar in lapack?

thanks a lot!

[Julien Langou]

Nope. Not "./".

I know to emulate " .* " with a BLAS call:

Code: Select all

cblas dgbmv( CblasColMajor, CblasNoTrans, m, m, 0, 0, 1, 0e0, X, 1, Y, 1, 0, 0e0, Z, 1);


I do not recommend this kind of trick though ... Most of the people are not able to read the previous line,
while they have no problem understanding the following:

Code: Select all

for(i=0;i<m;i++) Z[i] = X[i]*Y[i];


-julien.

[sven]

If you are happy to use Fortran, then it is part of the language since Fortran 90. That is, if x and y are 1-d arrays, then x/y is elementwise division. The array operations are a very nice feature of the language.

Sven.

[asp]

oh well... disappointing what else is there to say
thanks though anyway