svd_snowfall_test

svd_snowfall_test, a Fortran77 code which calls svd_snowfall(), which demonstrates the use of the Singular Value Decomposition (SVD) to analyze a set of historical snowfall data, with plots created by gnuplot().

Licensing:

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

Related Data and Programs:

svd_snowfall, a Fortran77 code which demonstrates the use of the Singular Value Decomposition (SVD) to analyze a set of historical snowfall data, with plots created by gnuplot().

Source Code:

• svd_snowfall_test.f, a sample calling program.
• svd_snowfall_test.sh, BASH commands to compile and run the sample program.
• svd_snowfall_test.txt, the output file.

The snowfall data itself must be read into the program from a file:

• snowfall.txt, the snowfall data.

The second test function writes "command" and "data" files that can be used by gnuplot to create plots.

• singular_values_commands.txt, a command file.
• singular_values_data.txt, a data file.
• singular_values.png, the resulting plot.

The third test function writes "command" and "data" files that can be used by gnuplot to create plots.

• approx_commands.txt, a command file.
• approx_data.txt, a data file.
• approx0.png, the 2012 snowfall (red).
• approx1.png, the 2012 snowfall (red) and rank 1 approximation (blue).
• approx2.png, the 2012 snowfall (red) and rank 2 approximation (blue).
• approx3.png, the 2012 snowfall (red) and rank 3 approximation (blue).
• approx4.png, the 2012 snowfall (red) and rank 4 approximation (blue).
• approx5.png, the 2012 snowfall (red) and rank 5 approximation (blue).

The fourth test function writes "command" and "data" files that can be used by gnuplot to create plots of the first 6 U modes, which form a basis for average snowfall as a function of the month.

• umode_commands.txt, a command file.
• umode_data.txt, a data file.
• umode1.png, basis vector 1 for snowfall as a function of month.
• umode2.png, basis vector 2 for snowfall as a function of month.
• umode3.png, basis vector 3 for snowfall as a function of month.
• umode4.png, basis vector 4 for snowfall as a function of month.
• umode5.png, basis vector 5 for snowfall as a function of month.
• umode6.png, basis vector 6 for snowfall as a function of month.

The fifth test function writes "command" and "data" files that can be used by gnuplot to create plots of the first 6 V modes, which form a basis for total yearly snowfall behavior as a function of the year.

• vmode_commands.txt, a command file.
• vmode_data.txt, a data file.
• vmode1.png, basis vector 1 for total yearly snowfall as a function of year.
• vmode2.png, basis vector 2 for total yearly snowfall as a function of year.
• vmode3.png, basis vector 3 for total yearly snowfall as a function of year.
• vmode4.png, basis vector 4 for total yearly snowfall as a function of year.
• vmode5.png, basis vector 5 for total yearly snowfall as a function of year.
• umode6.png, basis vector 6 for snowfall as a function of month.