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I am migrating from IMSL to MKL. I am trying to implement matrix-matrix and matrix-vector calculations using the BLAS.

I have a doubt about what the following statements mean:

(...)

use mkl95_precision, only: wp => dp

implicit none real(wp):: alpha, beta; !just an example of variables;

(...)

It seems that alpha and beta are double precision variables. There is any difference between the above statement and the following declaration? Which one should I use?

(...)

double precision alpha, beta;

(...)

Thank you in advance

Marcio Yamamoto

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Hi Marcio,

You are right. They are double precision. Both of those two be compiled. If you write alpha, beta as:

real(wp):: alpha, beta;

It make it some easierto changeto single precision code, and only need to change:

wp => DP to wp = SP

Thanks,

Chao

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Hi Marcio,

You are right. They are double precision. Both of those two be compiled. If you write alpha, beta as:

real(wp):: alpha, beta;

It make it some easierto changeto single precision code, and only need to change:

wp => DP to wp = SP

Thanks,

Chao

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The guys in Intel work up to midnight??!! You guys are my heroes! ;)

I was wondering if the statement "real(wp):: alpha, beta;" creates any special data structures/object which was necessary for the MKL/BLAS calculation. But it is not the case, right? Both statements generate exactly the same data structure: double precision array?

You should get some sleep, Chao.

Thank you again.

Marcio

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