/Fortran-examples

Some example codes in the Fortran language

Primary LanguageFortran

Fortran Examples

Here are some neat examples that is written in the Fortran language

makefile

Most of the time a Fortran program is written in many separate modules, procedures and files, with complicated dependency structure. This example shows that we can be organize the program into different directories, using a well designed makefile, with dependencies generated via makedepf90.

  • I'm using the gfortran compiler, with is freely available.
  • I'm also using the Numerical Recipe f90 codes as base for this example.
  • the modules .mod files will be output to the mod/ folder, and the object .o files will be output to the obj/ folder.
  • in the example program, I'm computing the volume of a hyper-sphere, with dimension and radius given.
  • the dependencies are generated using makedepf90

nr

This is just a test program, showing that we can include almost all Numerical-Recipe codes in the nr/ folder (without producing error). A check for the Fortran compiler flags used in the makefile.

  • note that not all NR fortran 90 codes are included in the nr/ folder
  • some of the NR codes have extra dependencies, I have excluded them
  • some fo the NR codes are not numerical algorithms, but some system validation codes, I have excluded as well.
  • the example used is similar to the 'makefile example'.

vegas

This is a minimum working example using the Numerical-Recipe vegas subroutine an introductory example to show how the vegas adaptive multi-dimensional numerical integration works

  • all vegas dependent codes in NR have been included in the vegas.f file.
  • the multidimensional integration calculates the volume of a 3D sphere with given radius.
  • the makefile is also minimized (but canbe modified for general use.

vegas-test

This is a simple program that tries to test the effectiveness of VEGAS

  • vegas is an adaptive monte-carlo multi-dimensional integration routine
  • this example uses a 4 dimensional integration, where each dimension integrates an oscillatory function
  • the integration strategies are divided into 3 categories: 1 - plain: 1 iteration, 2n samples 2 - iterative: 10 iteration, 2n/10 samples 3 - adaptive: warm-up 10 iteration, n/10 samples + final 1 iteration, n samples
  • all strategies should have similar total samples (maintain similar run time)

helper

This example include the usage and design of an object oriented class structure in Fortran The example is a few helper classes (modules) that will assist in a future program that I'm designing

  • the fourmom module creates a data type that work with Lorentz 4-momentums
  • the histogram module allows users to work with histogram book-keeping The above help classes are useful in cross-section calculations of high energy particle scatterings

omp-pi

This is a minimum working example that uses Fortran OpenMP parallelization

  • The example uses the Gregory-Leibniz series with mid-point integration to approximate the value of PI
  • the example uses the omp-lib library, please make sure to have libomp-dev installed
  • This example can be found online by John Burkardt, Florida State Univrsity, Department of Scientific Computing

glauber

A simple example to the optical Glauber model

  • atomic infomation of commonly used elements for heavy-ion collisions, which include uranium238, lead208, gold197, copper63, and aluminium27
  • the Density function return the nuclear mass density by using the Wood-Saxon distribution
  • the TA thickness and TAA overlap functions are calculated by 1D integration along the z-axis, using the Gaussian-Legendre quadrature in the gauss module
  • the example prints the thickness and overlap profile
  • the example also varifies two properties of the glauber module:

$$ \int dx dy ~ T_A(x,y) = M ,~~~ \int dx dy d^2b ~ T_{AA}(x,y,b) = M^2 $$

_where $(x,y)$ is the transverse position, $b$ the impact parameter, and $M$ the nuclear mass.

color

Code examples to show how to print colored texts using Fortran

  • the example comes with a simple procedure that takes a string and an integer color code as input and outputs the string with color
  • can print about 15 different colors (don't use same color as your terminal background though)
  • can only change the color of the font, not the background