RegridPixels.f90 : Main script cakecut_m.f90 and tools_m.f90 : Two modules called by RegridPixels.f90 Method.pdf : A slide to explain the method used in RegridPixels.f90 input/ : Test case, OMI HCHO pixels 2013 Aug-Sep output/ : Test case, outputs using 0.1 and 0.5 degree resolution plot/ : An R script to plot the outputs, and two plots with 0.1 and 0.5 degree resolution. You may want to comapre your results with those plots, just to make sure the code works well.
You may need to change the format of input files (around line 160 ) However, try to make change in run.sh, instead of RegridPixels.f90. By doing this you won't mess up the code.
gfortran -o RegridPixels.x cakecut_m.f90 tools_m.f90 RegridPixels.f90
./run.sh