From lai at lindaspaces.com  Mon Sep 26 19:05:50 2005
From: lai at lindaspaces.com (Jennifer Lai)
Date: Mon, 26 Sep 2005 13:05:50 -0400
Subject: [Rd] complex.h in R
In-Reply-To: <Pine.GSO.4.31.0509242129110.17364-100000@toucan.stats>
References: <Pine.GSO.4.31.0509242129110.17364-100000@toucan.stats>
Message-ID: <43382A6E.8020109@lindaspaces.com>

Hi,
I checked config.log and BLAS_LIBS was not set. However, I have set 
BLAS_LIBS='-L/usr/lib64 -lblas' in config.site file.
I can't figure out why BLAS_LIBS is not set, when PGI compiler is used. 
When gcc is used, BLAS_LIBS need not be set in config.site and 
automatically get picked up by the configuration script.

Here is a snapshot of the configuration script output (for buidling R 
with PGI compiler):
checking for complex.h... yes
checking for double complex... no
checking for sgemm_ in -L/usr/lib64 -lblas... yes
checking whether double complex BLAS can be used... no

Is there other thing I should look into in the config.log?
Your help is very much appreicated.


Thanks,
Jennifer


Prof Brian Ripley wrote:

>On Sat, 24 Sep 2005, Jennifer Lai wrote:
>
>  
>
>>Hi,
>>    How does complex.h used in R? Whether a compiler support complex.h
>>or not, does it affect R's performance?
>>    
>>
>
>complex.h will only used in future (2.2.0-to-be) versions of R, and only
>if configure finds enough C99 support. Otherwise R's own C-level complex
>support is used, as it always was.  One would expect the OS's support to
>be faster and more accurate (but one could be disappointed, we have
>found).
>
>  
>
>>I used PGI compiler to build
>>R-devel on AMD Opteron, but the configuration file failed to link BLAS
>>library despite the fact it is located in the usual location,
>>/usr/lib64.
>>    
>>
>
>Look in config.log to find out why.
>
>  
>
>>PGI said they don't support complex.h. R configuration
>>script printed out that doublecomplex is not supported.
>>    
>>
>
>That is *FORTRAN* DOUBLE COMPLEX, and that does affect the operation of R,
>as without it you will not have complex linear algebra support.
>
>  
>
>>Are "supporting
>>complex.h" and "linking BLAS library" related?
>>    
>>
>
>No.  They are completely orthoogonal concepts.
>
>  
>



[Rd] complex.h in R
Jennifer Lai