Intel® oneAPI Math Kernel Library
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I am new in this Community and I have same problems with the Math Kernel Library.

I hat loaded all libs and header Files from the Composer XE from Intel. The most Functions work but the Problem is the Functions “NUMROC” and “DESCINIT” find the Compiler not. And in no header file “.h” give as a link to this function.  

Can something me tell in which header file I found this function?


My problem two is I need a Function they are divide Matrixes, only the Elements divination by the same Element of Matrix two. (c[x,y]= a[x,y]/ b[x,y])

Give it a function in the Math Kernel Library them to this?

I can program this self but then is this not optimized.    



To the last give as in this Forum a search to find analogous problems.

Sorry I speak a bat English. I hope something can help my.

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2 Replies

Hello Robert,

Please have a look at some of the PBLAS examples. For a typical installation, you can find them at:

  • Linux: /opt/intel/composer_xe_2013.2.146/mkl/examples/pblasc
  • Windows: C:\Program Files (x86)\Intel\Composer XE 2013\mkl\examples\pblasc\source

(In general the examples are located at $MKLROOT/examples/pblasc.)

There you can see, that for example "pblas3_d_example.c" just calls a function "numroc_". Since the source code file is named ".c", the compiler translates the source in C-mode (as usual). As you know, the C language does not require to declare a function prototype. The trailing underscore at the function name is the way how the FORTRAN compiler mangles routine names. Although most FORTRAN compilers can be adjusted to avoid trailing underscores ("routine_"), it is the way most compilers expect the NETLIB symbols to be available. Intel MKL usually includes multiple versions of symbols to make it easier when Intel MKL is used with various compilers.

If you have further problems, let me know.
(Feel free to write in German ;-)


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one reason could be that the preprocessor symbol _WIN_ is not defined by the VS project. It handles a switch in the example header pblas_examples.h which in turn handles the name of the function symbols (trailing underscore, etc.).

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