Installation problems of Lapack in linux(fedora core 4) !

[taoyang]

Helllo,
My system is Linux (Fedora core 4) and I don't konw how to install the Lapack on my computer. I don't know which method I should follow.

The first way: yum install lapack. I have finished this step and the report as follows:
Updated: lapack.i386 0:3.0-36.fc4
Dependency Updated: blas.i386 0:3.0-36.fc4
Complete!
I don't know whether the lapack is installed successfully and how to test it and link the library.

Second way: I downloaded the lapack.tgz from netlib.org and make, error-reports occured as follows:
Timing square REAL LAPACK linear equation routines
xlintims < stime.in > stime.out 2>&1
make[1]: *** [stime.out] Error 127
make[1]: Leaving directory `/home/yangtao/LAPACK/TIMING'
make: *** [timing] Error 2

So ,can anybody help me? Thanks!

[Julien Langou]

Hello,

for the first way, you should have installed a liblapack.a (or .so) and libblas.a (or .so) somewhere (for example /usr/local/lib) in your system. So just have a look it should be there, otherwise ask Fedora support.

for the second way, your installation fails in the timing, which means that you have successfully compiled and tested the library. Try to apply the latest patch: http://www.netlib.org/lapack-dev/lapack--3.0--patch--10042002.tgz
you should be set. Note also that the timing are fairly long and if you do not want to use them, you can just skip this phase. (But I recommend you apply the patch.)

In the LAPACK directory, you have a lapack_???.a and a blas_???.a library. This is the LAPACK and BLAS libraries, you can rename them liblapack.a and librefblas.a if you want.

Note that if you care for performance when you use (and time) the LAPACK library, you should not link with the reference BLAS library (the blas_???.a in the LAPACK directory) but link LAPACK with an optimized BLAS library (see FAQ 2.5). The reference BLAS library is provided only for self-consistence of the package.

Julien

[yangtao]

Hello,
I have downloaded the latest patch and appled it. Thank you very much.
However, I am still very confused with the following problem:

First, in the LAPACK directory, typed "cp INSTALL/make.inc.LINUX make.inc" , then, typed "make". As a result, the process would stop after a few seconds when making tesing.

I had to use another way obtained from the Quick Installation Guide for LAPACK on Unix Systems step by step, those are:
cp INSTALL/make.inc.LINUX make.inc
make testing
make timing
(I don't konw whether the lapack is installed completely with this method)
All steps had no error reports. Does this mean that the lapack is installed on my computer successfully? If yes, why the first way typed "make" directly failed?
So, would you please tell me the difference between them?


Yang

[Julien Langou]

First, in the LAPACK directory, typed "cp INSTALL/make.inc.LINUX make.inc" , then, typed "make". As a result, the process would stop after a few seconds when making tesing.

Yes this is 'normal'.
The idea is that you want to use LAPACK with an optimized BLAS library not the reference BLAS library, so for the testing, you want to test LAPACK with an optimized BLAS library not the reference BLAS library.
So the default 'make' does not build the BLAS library by default. If you want to use it, you need to type 'make blaslib' by yourself. What you explained you figure out by yourself in the end of the post.

Does this mean that the lapack is installed on my computer successfully?

Yes, you are fine. You can go in the TESTING directory and check the .out files. They give you wether the testing succeeded or not. (Note they are some hard case in the test case and there is some known failures, see:
LAPACK/ScaLAPACK Development Forum: Post 43: lapack installation troubles...
)

Julien

[yangtao]

Thank you for giving me so much help!
I have checked the .out files in the TESTING directory. Almost in every .out file, there are some reports like as follows:

... ...
??? routines passed the tests of the error exits ( 33 tests done)
All tests for ??? routines passed the threshold ( 5966 tests run)
... ...

So, if the reports of the .out files are "normal", that is, I can use lapack safely now. IS IT RIGHT?

Thanks you very much indeed!

Yang

[Julien Langou]

So, if the reports of the .out files are "normal", that is, I can use lapack safely now. IS IT RIGHT?

Oh yes, you should be pretty safe. Have fun,
Julien

[yangtao]

Thank you again, Julien!
Yang