Mixed C++ Fortran Programming

This is another matrix multiplication project using the BLAS function dgemm. It is complied and run in an Ubuntu system. The set consists of two programs:  (right mouse click.  save target or link as) matrix_mult_cf.cpp fort_matmul_main.f The set calculates: C = A*B The C++ program matrix_mult_cf reads in two matrices, A & B. The input [...]

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Ubuntu Plotting Programs

I am evaluating plotting programs for Ubuntu.  I already have plotting capability via Matlab and Python/matplotlib running under Ubuntu. The Matlab export plot quality is ok but not great. So far my Python knowledge only extends to making static plots.  Identifying interactive, dynamic plotting methods in Python is still on my “to do” list. In [...]

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Linux Ubuntu Tips

The make install command is necessary to build certain software package. This may result in an error such as: /usr/local/lib: Permission denied The problem can be fixed by typing: su -c “make install” Then enter root password when prompted * * * The Update Manager may hang. An alternate method is to use the following [...]

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Install CBLAS in Ubuntu & Cygwin

CBLAS is C interface to the BLAS library. * * * Ubuntu Installation instructions: BLAS must be installed first. The instructions for BLAS are given at: Generalized Eigenvalue Problem & BLAS Next, wget http://www.netlib.org/blas/blast-forum/cblas.tgz tar zxf cblas.tgz Go to CBLAS folder. Open Makefiles.in in a text editor. Modify this line in Makefiles.in BLLIB = (specify [...]

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Matrix Multiplication in BLAS & CBLAS

Here is a program that uses dgemm to multiply two matrices:  matrix_mult.cpp The dgemm function is implemented using gsl blas. It can be compiled under Cygwin as: gcc -o matrix_mult_alt matrix_mult_alt.cpp -lgsl -lstdc++ And under Ubuntu as: gcc -o matrix_mult_alt matrix_mult_alt.cpp -lgsl -lgslcblas -lstdc++ * * * For benchmark comparison, here is a matrix multiplication [...]

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Lapack in Ubunutu

Blas and Lapack may be installed on an Ubuntu system using the instructions at: Generalized Eigenvalue Problem * * * C++ programs that use Lapack can be compiled in Terminal or Bash shell mode via: g++ file_in -o file_out -lgfortran -llapack -lm where file_in is the source code file_out is the output executable file In [...]

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Generalized Eigenvalue Problem

The goal of this project is to solve a “very large” generalized eigenvalue problem in a “reasonable” amount of time using library functions. The mass and stiffness matrices may be either dense or sparse. Optimum routines are desired for each case. Here is description of the libraries and packages gcc – GNU Compiler Collection for [...]

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Code::Blocks

Code::Blocks is a free C/C++ Integrated Development Environment (IDE). It may be downloaded from: http://www.codeblocks.org/ A number of compilers may be used with Code::Blocks. MinGW is a good choice for the compiler.  The Code::Blocks website has a bundled installion  file that includes MinGW. Note that MinGW stands for Minimalist GNU for Windows. MinGW is a [...]

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