r8gb

r8gb, an Octave code which carries out some basic linear algebra operations on R8GB matrices (real 64 bit precision general banded format).

Licensing:

The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.

Languages:

r8gb is available in a C version and a C++ version and a Fortran90 version and a MATLAB version and an Octave version and a Python version

Related Data and Programs:

r8gb_test

linear_algebra, MATLAB codes which carry out various linear algebra operations for matrices stored in a variety of formats.

Source Code:

• i4_log_10.m, returns the integer part of the logarithm base 10 of abs(X);
• r8_uniform_01.m, is a uniform random number generator;
• r8gb_det.m, computes the determinant of an R8GB matrix factored by R8GB_FA or R8GB_TRF;
• r8gb_dif2.m, returns the second difference matrix in R8GB format.
• r8gb_fa.m, performs a LINPACK style PLU factorization of an R8GB matrix;
• r8gb_indicator.m, returns an R8GB indicator matrix;
• r8gb_ml.m, computes A*x or A'*x after A has been factored by R8GB_FA;
• r8gb_mtv.m, multiplies a vector times an R8GB matrix;
• r8gb_mu.m, computes A*x or A'*x after A has been factored by R8GB_TRF;
• r8gb_mv.m, multiplies an R8GB matrix times a vector;
• r8gb_nz_num.m, counts the nonzeroes in an R8GB matrix;
• r8gb_print.m, prints an R8GB matrix.;
• r8gb_print_some.m, prints some of an R8GB matrix;
• r8gb_random.m, randomizes an R8GB matrix;
• r8gb_sl.m, solves a system factored by R8GB_FA;
• r8gb_to_r8ge.m, copies an R8GB matrix to an R8GE matrix;
• r8gb_to_r8s3.m, copies an R8GB matrix to an R8S3 matrix;
• r8gb_to_r8sp.m, copies an R8GB matrix to an R8SP matrix;
• r8gb_to_r8vec.m, copies an R8GB matrix to an R8VEC;
• r8gb_trf.m, performs a LAPACK style PLU factorization of an R8GB matrix;
• r8gb_trs.m, solves a linear system factored by R8GB_TRS;
• r8gb_zeros.m, zeros an R8GB matrix;
• r8ge_det.m, computes the determinant of a factored R8GE matrix;
• r8ge_fa.m, factors an R8GE matrix;
• r8ge_print.m, prints an R8GE matrix;
• r8ge_print_some.m, prints some of an R8GE matrix;
• r8ge_random.m, returns a random R8GE matrix;
• r8ge_to_r8gb.m, converts an R8GE matrix to an R8GB matrix;
• r8ge_to_r8vec.m, converts an R8GE matrix to an R8VEC;
• r8s3_print.m, prints an R8S3 matrix;
• r8s3_print_some.m, prints some of an R8S3 matrix;
• r8sp_print.m, prints an R8SP matrix;
• r8sp_print_some.m, prints some of an R8SP matrix;
• r8vec_indicator1.m, sets an R8VEC to the indicator1 vector;
• r8vec_print.m, prints an R8VEC;
• r8vec_to_r8gb.m, converts an R8VEC to an R8GB matrix;
• r8vec_to_r8ge.m, converts an R8VEC to an R8GE matrix;
• r8vec2_print.m, prints a pair R8VEC's;