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Nasser M. Abbasi

July 2, 2015 page compiled on July 2, 2015 at 2:25am

Contents

1 using OPENGL with Fortran
 1.1 source code
 1.2 description
 1.3 building the Fortran OPENGL binding
 1.4 building a client fortran program using the OPENGL binding
  1.4.1 dynamic build
  1.4.2 static build
 1.5 Examples of statically prebuild Fortran programs build with openGL binding
2 small examples of Fortran code
 2.1 f01.f90
 2.2 f02.f90
 2.3 f03.f90
 2.4 f04.f90 with mod file
 2.5 f05.f90
 2.6 f06.f90
 2.7 f07.f90
 2.8 f08.f90
 2.9 f08a.f90
 2.10 f09.f90
 2.11 f10.f90
 2.12 f11.f90
3 build Fortran binding to gsl
4 compiling with pgplot
5 install gfortran
6 my Fortran cheat sheet notes

1 using OPENGL with Fortran

1.1 source code

This zip file contains the source code and examples and scripts needed to build client Fortran program using the Fortran 2003 openGL binding

nma_fortran_opengl.zip

The above is a slight modification based on the original binding located at

http://www-stone.ch.cam.ac.uk/pub/f03gl/index.xhtml

based on work by Anthony Stone, Aleksandar Donev and the original f90 open GL binding by William F. Mitchell.

What I did is document the F2003 openGL binding with diagrams below, made small code changes to make build with F2008 and build the examples in it as static to make it easier for someone to download and run without having to have openGL installed on their Linux. This was done for Linux only not for windows. Below is more description of my changes to the binding.

The executables of the examples are in the above zip file. I added .exe to the names just to make it more clear. These are linux executables, not windows.

1.2 description

This describes how to use 2003 opengl with Fortran and few examples I wrote using this API as I learning openGL. First a description of the build structure is given. This is the description based on my own layout of the official binding obtained from http://www-stone.ch.cam.ac.uk/pub/f03gl/index.xhtml

I have made small changes to the file naming (mixed case changed to all lower case) since it is less confusing this way, as Fortran is case insensitive and now the file names and the module names all match.

In addition, I broke one module file into 2 files so that there is 1-1 correspondence with file name and module name.

Some code changes are made to the binding files to make them build with std=f2008.

The description below reflects what I have in the above zip file not the original and official Fortran 2003 openGL binding.

There are now 4 Fortran files that make up the Fortran 2003 binding, and one C file. They are

1.
opengl_kinds.f90.txt generates opengl_kinds.mod, all other files USE this one.
2.
opengl_glu.f90.txt generates opengl_glu.mod
3.
opengl_gl.f90.txt generates opengl_gl.mod
4.
opengl_freeglut.f90.txt note: this generates opengl_glut.mod and not opengl_freeglut.mod
5.
glut_fonts.c.txt generates glut_fonts.o only

This picture below shows the layout of the binding tree as I have it now (again, this is slightly different naming from the official tar file)

  
        $HOME/
          |
          |
         fortran_binding/
          |
          |
       opengl_freeglut.f90 (USE opengl_kinds)  ---> opengl_freeglut.o
                                                    opengl_glut.mod
  
       opengl_gl.f90 (USE opengl_kinds)        ---> opengl_gl.o
                                                    opengl_gl.mod
  
       opengl_glu.f90 (USE opengl_kinds)       ---> opengl_glu.o
                                                    opengl_glu.mod
  
       opengl_kinds.f90                        ---> opengl_kinds.o
                                                    opengl_kinds.mod
  
       glut_fonts.c --> glut_fonts.o
  

A client program needs to link against the 5 object files

  opengl_glut.o, opengl_gl.o, opengl_glu.o, opengl_kinds.o, glut_fonts.o

and the client will contain USE opengl_gl, USE opengl_glut and USE opengl_glu in the source to be able to access the functions provided by these bindings.

Therefore, a typical structure of a Fortran program that uses opengl will be as follows

  
          CLIENT                               B  I N D I N G
         ========                ====================================================
  
  
         main.f90                 opengl_gl.mod                opengl_kinds.mod
    +---------------------+      +----------------------+     +---------------------+
    |program main         |----->|MODULE opengl_glu     |     |MODULE opengl_kinds  |
    | USE opengl_gl       |      |USE opengl_kinds      |---> |                     |
    | USE opengl_glut     |      |.....                 |     |                     |
    | USE opengl_glu      |      +----------------------+     |                     |
    |                     |        opengl_gl.o                |                     |
    | implicit none       |                                   |                     |
    |  ....               |        opengl_glut.mod            |                     |
    |                     |      +----------------------+     |                     |
    |CALL glutInit()      |      |MODULE opengl_glut    |     |                     |
    |CALL glLoadIdentity()|----->|USE opengl_kinds      |---> |                     |
    |CALL gluBeginCurve() |      |.....                 |     |                     |
    |                     |      +----------------------+     |                     |
    |                     |         open_glut.o               |                     |
    |                     |                                   |                     |
    |  ....               |          opengl_glu.mod           |                     |
    |                     |      +----------------------+     |                     |
    |                     |      |MODULE opengl_glu     |     |                     |
    |                     |----->|USE opengl_kinds      |---> |                     |
    |                     |      |.....                 |     |                     |
    |                     |      +----------------------+     |                     |
    |                     |          open_glu.o               |                     |
    |                     |                                   +---------------------+
    |end program main     |                                       opengl_kinds.o
    +---------------------+
  
                                                                   glut_fonts.c
                                                              +---------------------+
                                                              |#include <glut.h>    |
                                                              |...                  |
                                                              +---------------------+
                                                                   glut_font.o

In the above diagram, the client program main.f90 needs to link to the above 4 object files generated from the 4 Fortran files, and against the object file generated from the one C file glut_fonts.o

The above shows the object files that needs to be linked against. In addition, one needs to link to the opengl and glut and X libraries of course. For static linking, other libraries are needed. Diagram below shows all libraries needed, and a script is including below to do that.

The diagram below shows everything that is needed to compile and link against.

This assumes a Linux 32 bit system. This is based on Linux mint 32 bit. On different Linux distributions or on 64 bit, the tree will can and will look a little different depending on the distribution.

To compile the C file glut_fonts.c the file GL/glut.h is needed.

In the diagram below it is assumed that main.f90 is located in your own folder, say $HOME/src and that the Fortran opengl binding files are located in $HOME/fortran_opengl.

The following diagram shows all the files needed to build an executable as shared or static. This is the layout on Linux 32 bit (Linux Mint 13)

  
                                   /
                                   |
                                   usr/
                                   |
                                   |
       +---------------------------+----+---------+-----------------------+
       |                                |         |                       |
      $HOME/                          /include   /lib                   gnat/
       |                                |         |                       |
       |                                |         |                      lib/
       |                                |         |                       |
       |                                |         |                  libstdc++.so(.a)
       |                                |         |
       |                                |         |
       +-------------+                  |         +----------------+---------------+
      src/       fortran_opengl/        |         |                |               |
       |             |                 GL/       gcc/        i386-linux-gnu/       |
       |             |                  |         |                |          libglut.so(.a)
      main.f90    opengl_freeglut.f90   |   i686-linux-gnu/  +-------------+
      main.o      opengl_freeglut.o     |         |          |             |
                  opengl_glut.mod      glut.h     |        mesa/           |
                                       glu.h      |          |             |
                  opengl_gl.f90        gl.h       |       libGL.so(.a)   libGLU.so(.a)
                  opengl_gl.o          freeglut.h |                      libXaw7.so(.a)
                  opengl_gl.mod        ....       |                      libXt.so(.a)
                                                  |                      libXmu.so(.a)
                  opengl_glu.f90                 4.6/                    libXi.so(.a)
                  opengl_glu.o                    |                      libXext.so(.a)
                  opengl_glu.mod                  |                      libX11.so(.a)
                                              libgfortran.a              libm.so(.a)
                  opengl_kinds.f90                                       libpthread.so(.a)
                  opengl_kinds.o                                         libXdmcp.so(.a)
                  opengl_kinds.mod                                       libXau.so(.a)
                                                                         libxcb.so(.a)
                  glut_fonts.c                                           libdl.so(.a)
                  glut_fonts.o                                           libgfortran.so
  

1.3 building the Fortran OPENGL binding

Building the openGL binding only is simple. It is just compiling the above 5 files to generate the 5 object files and the 4 .mod Fortran files. The following bash script accomplishes this

build_fortran_opengl_binding.sh.txt

I did not use Makefiles here in order to make it easier. Any one who is familiar with Makefiles can easily use these scripts to make a Makefile from them.

To building the binding, change to the directory where the Fortran OPENGL binding is located and execute the build bash script

  ./build_fortran_opengl_binding.sh

Here is the listing of the above script

  #!/bin/bash
  
  #the compile flags
  FFLAGS="-Wall -Wextra -pedantic -fcheck=all
          -fcheck=do -fwhole-file -funroll-loops -ftree-vectorize
          -Wsurprising -Wconversion-extra"
  
  #compile the fortran files
  gfortran -std=f2008 $FFLAGS -c opengl_kinds.f90  #must be first one
  gfortran -std=f2008 $FFLAGS -c opengl_freeglut.f90
  gfortran -std=f2008 $FFLAGS -c opengl_glu.f90
  gfortran -std=f2008 $FFLAGS -c opengl_gl.f90
  
  gcc  -Wall -Wextra -pedantic  -I/usr/include -c glut_fonts.c

1.4 building a client fortran program using the OPENGL binding

After building the Fortran OPENGL binding as shown above, now you can build a client program that uses it.

Two ways to build a client program are given. One is a dynamic build, which builds against the shared opengl and X libraries (.so), then a static build which uses the .a libraries.

The static build would be better if you want to send the executable to someone else to run the program on their computer which might not have all the libraries installed or different versions.

1.4.1 dynamic build

With all the above in place, the following script builds a client program simple3.f90 program that uses Fortran openGL

build_dynamic_opengl_client_linux_mint.sh.txt

Change to the directory where you have your client Fortran program and type

  ./build_dynamic_opengl_client_linux_mint.sh

Now run the program generated from the above script

  ./simple3

If you get error like this

  OpenGL Warning: XGetVisualInfo returned 0 visuals

then try the following command LIBGL_ALWAYS_INDIRECT=1  ./simple3

1.4.2 static build

To build static program, all what is needed is to link statically against the .a libraries instead of the shared libraries. But now the order of libraries is important.

The following script accomplishes this

build_static_opengl_client_linux_mint.sh.txt

Change to the directory where you have your client Fortran program and type

./build_static_opengl_client_linux_mint.sh

1.5 Examples of statically prebuild Fortran programs build with openGL binding

This table includes the examples from the official openGL fortran 2003 binding build statically on Linux. Each example has a screen shot and link to the source code and the executable. You can download the executable to Linux and run it. Hopefully it will run as is since it is statically linked.

I added .exe extension to the executable since some browsers have a bug in them where the file will be corrupted during download if it is binary but does not have .exe extension. This was the case using Firefox on linux.

To download the .exe, do SAVE AS and save it on your Linux file system, then run it as you would run any executable on linux.

All of these executables are in the above zip file. So if you downloaded the zip file, these are in there already.



RandomSphere_FreeGLUT.f90

executable randomspher_freeglut_main_ static_build.exe

PIC

scube.f90

scube_mod.f90 executable scube_static_ build.exe

PIC



simple2.f90

executable simple2_static_build.exe

PIC

blender_main.f90

blender.f90

executable blender_main_static_build.exe

PIC



plotfunc.f90

function_plotter.f90

modview.f90

executable plotfunc_static_build.exe

PIC

randomspher_freeglut_main.f90

RandomSphere_FreeGLUT.f90

executable randomspher_freeglut_main_ static_build.exe

PIC



stars.f90

stars_mod.f90

executable stars_static_build.exe

PIC

view_demo.f90

view_demo_callbacks.f90

view_modifier.f90

executable view_demo_static_build.exe

PIC



2 small examples of Fortran code

All these examples are build with this Makefile

2.1 f01.f90

f01.f90

  !-- matrix transpose in Fortran
  !-- Nasser M. Abbasi Feb 12, 2012
  !--
  !-- gfortran -std=f2008 f01.f90
  
  program f01
    implicit none
    integer :: B(2,3),A(3,2);
  
    B(1,:) = [1,2,3]
    B(2,:) = [3,4,5]
  
    CALL print_matrix(B)
  
    A = transpose(B)
  
    CALL print_matrix(A)
  
  CONTAINS
    subroutine print_matrix(A)
      implicit none
      integer, intent(in) :: A(:,:)
      integer :: i
  
      PRINT *,'--------------------'
      DO i = 1,size(A,1)
         print '(3i3)', A(i,:)
      END DO
  
    end subroutine print_matrix
  end program f01
  
  $./a.out
   --------------------
    1  2  3
    3  4  5
   --------------------
    1  3
    2  4
    3  5
  

2.2 f02.f90

f02.f90

  !-- matrix, matrix multiply
  !-- Nasser M. Abbasi Feb 12, 2012
  !--
  !-- gfortran -std=f2008 f02.f90
  
  program f02
    implicit none
    integer :: A(2,3)
  
    A(1,:) = [1,2,3]
    A(2,:) = [3,4,5]
  
    CALL print_matrix( matmul(A, transpose(A)) )
  
  CONTAINS
    subroutine print_matrix(A)
      implicit none
      integer, intent(in) :: A(:,:)
      integer :: i
  
      DO i = 1,size(A,1)
         print '(3i3)', A(i,:)
      END DO
  
    end subroutine print_matrix
  end program f02
  
  $gfortran -std=f2008 f02.f90
  $./a.out
   14 26
   26 50

2.3 f03.f90

f03.f90

  Translate this Matlab line to Fortran:
  
  exp((0:1/100:1)*pi*2*sqrt(-1))
  
  PROGRAM f03
  IMPLICIT none
  INTEGER, PARAMETER :: dp = SELECTED_REAL_KIND(15)
  COMPLEX, PARAMETER :: arg=CMPLX(0_dp,4.0_dp*ACOS(0.0_dp),KIND=KIND(dp))
  INTEGER, PARAMETER :: N=5
  INTEGER :: i
  REAL(KIND=dp), PARAMETER :: x(N+1) = (/ (DBLE(i)/DBLE(N), i=0,N)/)
  
  
     DO i=1,SIZE(x)
       PRINT*, exp(x(i)*arg)
     END DO
  
  END PROGRAM f03
  
  >gfortran   -fcheck=all -Wall -Wconversion -Wextra -Wconversion-extra -pedantic f11.f90
  >./a.out
   (  1.0000000000000000     ,  0.0000000000000000     )
   ( 0.30901696111734539     , 0.95105652710120292     )
   (-0.80901703548360204     , 0.58778519571125987     )
   (-0.80901693271195796     ,-0.58778533716428760     )
   ( 0.30901712740535175     ,-0.95105647307094476     )
   ( 0.99999999999998468     ,  1.7484556000744883E-007)
  
  Matlab
  
  >> exp((0:1/5:1)*pi*2*sqrt(-1)).'
  
    1.000000000000000 + 0.000000000000000i
    0.309016994374947 + 0.951056516295154i
   -0.809016994374947 + 0.587785252292473i
   -0.809016994374947 - 0.587785252292473i
    0.309016994374947 - 0.951056516295154i
    1.000000000000000 - 0.000000000000000i
  

2.4 f04.f90 with mod file

f04.f90 foo_mod.f90

  
  --- file  foo_mod.f90 ---------
  
  module foo_mod
  !-- Overload 2 subroutine names
    implicit none
    interface foo
      procedure foo_i,foo_c
    end interface
  contains
     subroutine foo_i(arg)
       integer, intent(in) :: arg
       print *, arg
     end subroutine
  
     subroutine foo_c(arg)
       complex, intent(in) :: arg
       print *, arg
     end subroutine
  end module foo_mod
  -------------------------

and a second file

  --- file  f04.f90 ---------
  program f04
    use foo_mod
    implicit none
  
    complex, parameter :: x= CMPLX(0,2.0*ACOS(0.0))
    integer, parameter :: y=5
  
    CALL foo(x)
    CALL foo(y)
  
  end program f04
  -----------------------
  
  $./a.out
   (  0.0000000    ,  3.1415927    )
             5

2.5 f05.f90

f05.f90

  --------- file f05.f90 -----------------------
  program f05
  !-- Overload 2 subroutine names as above but using one file
  !-- but need to use std=gnu to compile
  
    implicit none
  
    complex, parameter :: x= CMPLX(0,2.0*ACOS(0.0))
    integer, parameter :: y=5
  
    interface foo
       procedure foo_c, foo_i
    end interface foo
  
    CALL foo(x)
    CALL foo(y)
  
  contains
    subroutine foo_i(arg)
      integer, intent(in) :: arg
      print *, arg
    end subroutine
  
    subroutine foo_c(arg)
      complex, intent(in) :: arg
      print *, arg
    end subroutine
  
  end program f05

2.6 f06.f90

f06.f90

  --------- file f06.f90 -----------------------
  !-- It is possible to put the module inside
  !-- the same file as the program that uses it
  !-- if it is only the program that needs it
  program f06
    use foo_mod
    implicit none
  
    complex, parameter :: x= CMPLX(0,2.0*ACOS(0.0))
    integer, parameter :: y=5
  
    CALL foo(x)
    CALL foo(y)
  
  end program f06
  
  module foo_mod
    implicit none
    interface foo
      procedure foo_i,foo_c
    end interface
  contains
     subroutine foo_i(arg)
       integer, intent(in) :: arg
       print *, arg
     end subroutine
  
     subroutine foo_c(arg)
       complex, intent(in) :: arg
       print *, arg
     end subroutine
  end module foo_mod
  --------- end file f06.f90 -----------------------
  
  $./a.out
   (  0.0000000    ,  3.1415927    )
             5

2.7 f07.f90

f07.f90

  --------- file f07.f90 -----------------------
  !-- using select_int_kind
  program f07
    implicit none
  
    integer(selected_int_kind(5))  :: i=16
    integer(selected_int_kind(10)) :: j=16
  
    CALL foo(i)
    CALL foo(j)
  
  contains
    subroutine foo(arg)
      integer(selected_int_kind(5)), intent(in) :: arg
      print *, arg
    end subroutine foo
  
  end program f07
  --------- end file f07.f90 -----------------------

2.8 f08.f90

f08.f90

  !-- showing how to use Fortran for vectored operations
  !-- equations work on vectors, no need for loop
  !-- showing how to use Fortran for vectored operations
  !-- equations work on vectors, no need for loop
  program f08
    implicit none
  
    integer, parameter :: N = 7
    real   , parameter :: D(N) = [-0.2,1.0,1.5,3.0,-1.0,4.2,3.1]
    real   , parameter :: H(N) = [2.1,2.4,1.8,2.6,2.6,2.2,1.8]
    real   , parameter :: pi = 2.0* ACOS(0.0)
    real               :: V(N)
  
    V = (1.0/12.0)*pi*(D**2)*H
    print *, v
  
  
  end program f08
  
  $./a.out
  2.19911486E-02 0.62831855 1.0602875  6.1261053  0.68067843  10.159910  4.5286055

2.9 f08a.f90

f08_a.f90

  !-- As above, but uses allocatable
  !-- showing how to use Fortran for vectored operations
  !-- equations work on vectors, no need for loop
  program f08_a
    implicit none
  
    integer, parameter :: N = 7
    real, parameter :: D(N) = [-0.2,1.0,1.5,3.0,-1.0,4.2,3.1]
    real, parameter  :: H(N) = [2.1,2.4,1.8,2.6,2.6,2.2,1.8]
    real, parameter :: pi = 2.0* ACOS(0.0)
    real, allocatable :: V(:)
  
    V = (1.0/12.0)*pi*(D**2)*H
    print *, v
  
  end program f08_a

2.10 f09.f90

f09.f90

  !-- print exp(n*I*Pi/4) for n=1..10, where I is the sqrt(-1)
  program f09
     implicit none
     INTEGER, PARAMETER :: DP = KIND(0.0D0)
     integer :: n
     real(kind=DP), parameter  :: pi = 4.D0*DATAN(1.D0)
     complex, parameter        :: I = CMPLX(0, 1)
     DO n = 1,10
        print *, exp(n*I*pi/4.0D0)
     END DO
  end program f09
  
  $gfortran -std=f2003 -Wextra -Wall -pedantic -fcheck=all \
           -march=native  -Wsurprising -Wconversion  f09.f90
  $./a.out
   ( 0.70710678118654757     , 0.70710678118654746     )
   ( 6.12303176911188629E-017,  1.0000000000000000     )
   (-0.70710678118654746     , 0.70710678118654757     )
   ( -1.0000000000000000     , 1.22460635382237726E-016)
   (-0.70710678118654768     ,-0.70710678118654746     )
   (-1.83690953073356589E-016, -1.0000000000000000     )
   ( 0.70710678118654735     ,-0.70710678118654768     )
   (  1.0000000000000000     ,-2.44921270764475452E-016)
   ( 0.70710678118654768     , 0.70710678118654735     )
   ( 3.06151588455594315E-016,  1.0000000000000000     )
  $

2.11 f10.f90

f10.f90

  !-- shows how to declare 2D array in place
  !-- thanks to help from James Van Buskirk and glen herrmannsfeldt
  !-- from comp.lang.fortran
  program f10
  implicit none
  
  INTEGER, dimension(2,3)::A = &
     reshape(   &
       [2,3,4 , &
        4,0,7], &
        shape(A) , order = [2,1])
  
  integer :: i
  
  do i=LBOUND(A, 1),UBOUND(A, 1)
     print *,A(i,:)
  end do
  
  end program f10
  
  
  >./a.out
             2           3           4
             4           0           7
  

2.12 f11.f90

f11.f90

Example of using advance='no'

  PROGRAM f11
     IMPLICIT none
     INTEGER :: i
     INTEGER, DIMENSION(2,3)::B = &
          RESHAPE([2,3,4 , &
                   4,0,7], &
          SHAPE(B) , ORDER = [2,1])
  
    DO i=1,2
       WRITE(*,'(A)',ADVANCE='no') '['
       WRITE(*,  '(*(I2))', ADVANCE='no')  B(i,:)
       WRITE(*,'(A)' ) ' ]'
    END DO
  END PROGRAM f11
  
  >./f11
  [ 2 3 4 ]
  [ 4 0 7 ]
  

3 build Fortran binding to gsl

  
  trying to build gsl fortran, but get errors
  
  $./configure --f90 gfortran --gsl /usr/local
    Using /usr/bin/gfortran as Fortran compiler
    Using /usr/bin/gcc as C compiler
    Using GSL library located in /usr/local/lib
    Installation target path is /usr/local.
  Configuration successful. Now run make to build,
  or make test to run test suite. Enjoy!
  
  $make
  gfortran   -c  fgsl.f90
  gcc -c -I/usr/local/include   -o fgsl_utils.o fgsl_utils.c
  fgsl_utils.c:9:28: fatal error: gsl/gsl_odeiv2.h: No such file or directory
  compilation terminated.
  make: *** [fgsl_utils.o] Error 1
  $
  

4 compiling with pgplot

installed pgplot using synaptic package manager. This is below how to build the fortran example shown at the pgplot website

  
  ----- ex1.f --------------------
  PROGRAM EX1
        INTEGER PGOPEN, I
        REAL XS(9), YS(9), XR(101), YR(101)
  C Compute numbers to be plotted.
  
        DO 10 I=1,101
            XR(I) = 0.1*(I-1)
            YR(I) = XR(I)**2*EXP(-XR(I))
   10   CONTINUE
        DO 20 I=1,9
            XS(I) = I
            YS(I) = XS(I)**2*EXP(-XS(I))
   20   CONTINUE
  
  C Open graphics device.
        IF (PGOPEN('?') .LT. 1) STOP
  C Define coordinate range of graph (0 < x < 10, 0 < y < 0.65),
  C and draw axes.
        CALL PGENV(0., 10., 0., 0.65,  0,  0)
  C Label the axes (note use of \u and \d for raising exponent).
        CALL PGLAB('x', 'y', 'PGPLOT Graph: y = x\u2\dexp(-x)')
  C Plot the line graph.
        CALL PGLINE(101, XR, YR)
  C Plot symbols at selected points.
        CALL PGPT(9, XS, YS, 18)
  C Close the graphics device.
        CALL PGCLOS
        END

The command used is

  gfortran ex1.f -L/usr/lib -L/usr/lib/i386-linux-gnu -lpgplot -lcpgplot -lX11 -lpng
  \end{Verbatim]
  
  This was done on
  \begin{Verbatim}[samepage=true]
  $uname -a
  Linux me-VirtualBox 3.0.0-12-generic #20-Ubuntu SMP Fri Oct 7 14:50:42 UTC 2011 i686 i686 i386 GNU/Linux
  
  $gfortran -v
  Using built-in specs.
  COLLECT_GCC=gfortran
  COLLECT_LTO_WRAPPER=/usr/lib/gcc/i686-linux-gnu/4.6.1/lto-wrapper
  Target: i686-linux-gnu
  Configured with: ../src/configure -v --with-pkgversion='Ubuntu/Linaro 4.6.1-9ubuntu3' --with-bugurl=file:///usr/share/doc/gcc-4.6/README.Bugs --enable-languages=c,c++,fortran,objc,obj-c++,go --prefix=/usr --program-suffix=-4.6 --enable-shared --enable-linker-build-id --with-system-zlib --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --with-gxx-include-dir=/usr/include/c++/4.6 --libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu --enable-libstdcxx-debug --enable-libstdcxx-time=yes --enable-plugin --enable-objc-gc --enable-targets=all --disable-werror --with-arch-32=i686 --with-tune=generic --enable-checking=release --build=i686-linux-gnu --host=i686-linux-gnu --target=i686-linux-gnu
  Thread model: posix
  gcc version 4.6.1 (Ubuntu/Linaro 4.6.1-9ubuntu3)
  $

5 install gfortran

  >which gfortran
  >gfortran
  The program 'gfortran' is currently not installed. You can install it by typing:
  sudo apt-get install gfortran
  >sudo apt-get install gfortran
  Reading package lists... Done
  Building dependency tree
  Reading state information... Done
  The following extra packages will be installed:
    cpp-4.8 gcc-4.8 gcc-4.8-base gfortran-4.8 libasan0 libatomic1 libc-dev-bin libc6-dev libgcc-4.8-dev libgcc1
    libgfortran-4.8-dev libgfortran3 libgomp1 libitm1 libquadmath0 libstdc++6
  Suggested packages:
    gcc-4.8-locales gcc-4.8-multilib libmudflap0-4.8-dev gcc-4.8-doc libgcc1-dbg libgomp1-dbg libitm1-dbg
    libatomic1-dbg libasan0-dbg libtsan0-dbg libbacktrace1-dbg libquadmath0-dbg libmudflap0-dbg gfortran-multilib
    gfortran-doc gfortran-4.8-multilib gfortran-4.8-doc libgfortran3-dbg glibc-doc
  The following NEW packages will be installed:
    gfortran gfortran-4.8 libc-dev-bin libc6-dev libgfortran-4.8-dev
  The following packages will be upgraded:
    cpp-4.8 gcc-4.8 gcc-4.8-base libasan0 libatomic1 libgcc-4.8-dev libgcc1 libgfortran3 libgomp1 libitm1
    libquadmath0 libstdc++6
  12 upgraded, 5 newly installed, 0 to remove and 193 not upgraded.
  Need to get 28.0 MB of archives.
  After this operation, 38.0 MB of additional disk space will be used.
  Do you want to continue [Y/n]?
  Get:1 http://archive.ubuntu.com/ubuntu/ saucy-updates/main libquadmath0 i386 4.8.1-10ubuntu9 [218 kB]
  Get:2 http://archive.ubuntu.com/ubuntu/ saucy-updates/main libitm1 i386 4.8.1-10ubuntu9 [36.8 kB]
  Get:3 http://archive.ubuntu.com/ubuntu/ saucy-updates/main libgomp1 i386 4.8.1-10ubuntu9 [29.0 kB]
  Get:4 http://archive.ubuntu.com/ubuntu/ saucy-updates/main gcc-4.8-base i386 4.8.1-10ubuntu9 [16.7 kB]
  Get:5 http://archive.ubuntu.com/ubuntu/ saucy-updates/main libstdc++6 i386 4.8.1-10ubuntu9 [335 kB]
  Get:6 http://archive.ubuntu.com/ubuntu/ saucy-updates/main libgfortran3 i386 4.8.1-10ubuntu9 [324 kB]
  Get:7 http://archive.ubuntu.com/ubuntu/ saucy-updates/main libatomic1 i386 4.8.1-10ubuntu9 [9,694 B]
  Get:8 http://archive.ubuntu.com/ubuntu/ saucy-updates/main libasan0 i386 4.8.1-10ubuntu9 [76.2 kB]
  Get:9 http://archive.ubuntu.com/ubuntu/ saucy-updates/main cpp-4.8 i386 4.8.1-10ubuntu9 [5,657 kB]
  Get:10 http://archive.ubuntu.com/ubuntu/ saucy-updates/main gcc-4.8 i386 4.8.1-10ubuntu9 [6,450 kB]
  Get:11 http://archive.ubuntu.com/ubuntu/ saucy-updates/main libgcc-4.8-dev i386 4.8.1-10ubuntu9 [2,795 kB]
  Get:12 http://archive.ubuntu.com/ubuntu/ saucy-updates/main libgcc1 i386 1:4.8.1-10ubuntu9 [53.7 kB]
  Get:13 http://archive.ubuntu.com/ubuntu/ saucy-updates/main libgfortran-4.8-dev i386 4.8.1-10ubuntu9 [390 kB]
  Get:14 http://archive.ubuntu.com/ubuntu/ saucy/main libc-dev-bin i386 2.17-93ubuntu4 [74.9 kB]
  Get:15 http://archive.ubuntu.com/ubuntu/ saucy/main libc6-dev i386 2.17-93ubuntu4 [5,519 kB]
  Get:16 http://archive.ubuntu.com/ubuntu/ saucy-updates/main gfortran-4.8 i386 4.8.1-10ubuntu9 [5,984 kB]
  Get:17 http://archive.ubuntu.com/ubuntu/ saucy/main gfortran i386 4:4.8.1-2ubuntu3 [1,206 B]
  Fetched 28.0 MB in 20s (1,391 kB/s)
  (Reading database ... 147551 files and directories currently installed.)
  Preparing to replace libquadmath0:i386 4.8.1-10ubuntu8 (using .../libquadmath0_4.8.1-10ubuntu9_i386.deb) ...
  Unpacking replacement libquadmath0:i386 ...
  Preparing to replace libitm1:i386 4.8.1-10ubuntu8 (using .../libitm1_4.8.1-10ubuntu9_i386.deb) ...
  Unpacking replacement libitm1:i386 ...
  Preparing to replace libgomp1:i386 4.8.1-10ubuntu8 (using .../libgomp1_4.8.1-10ubuntu9_i386.deb) ...
  Unpacking replacement libgomp1:i386 ...
  Preparing to replace gcc-4.8-base:i386 4.8.1-10ubuntu8 (using .../gcc-4.8-base_4.8.1-10ubuntu9_i386.deb) ...
  Unpacking replacement gcc-4.8-base:i386 ...
  Setting up gcc-4.8-base:i386 (4.8.1-10ubuntu9) ...
  (Reading database ... 147551 files and directories currently installed.)
  Preparing to replace libstdc++6:i386 4.8.1-10ubuntu8 (using .../libstdc++6_4.8.1-10ubuntu9_i386.deb) ...
  Unpacking replacement libstdc++6:i386 ...
  Preparing to replace libgcc1:i386 1:4.8.1-10ubuntu8 (using .../libgcc1_1%3a4.8.1-10ubuntu9_i386.deb) ...
  Unpacking replacement libgcc1:i386 ...
  Setting up libgcc1:i386 (1:4.8.1-10ubuntu9) ...
  Setting up libstdc++6:i386 (4.8.1-10ubuntu9) ...
  Processing triggers for libc-bin ...
  (Reading database ... 147551 files and directories currently installed.)
  Preparing to replace libgfortran3:i386 4.8.1-10ubuntu8 (using .../libgfortran3_4.8.1-10ubuntu9_i386.deb) ...
  Unpacking replacement libgfortran3:i386 ...
  Preparing to replace libatomic1:i386 4.8.1-10ubuntu8 (using .../libatomic1_4.8.1-10ubuntu9_i386.deb) ...
  Unpacking replacement libatomic1:i386 ...
  Preparing to replace libasan0:i386 4.8.1-10ubuntu8 (using .../libasan0_4.8.1-10ubuntu9_i386.deb) ...
  Unpacking replacement libasan0:i386 ...
  Preparing to replace cpp-4.8 4.8.1-10ubuntu8 (using .../cpp-4.8_4.8.1-10ubuntu9_i386.deb) ...
  Unpacking replacement cpp-4.8 ...
  Preparing to replace gcc-4.8 4.8.1-10ubuntu8 (using .../gcc-4.8_4.8.1-10ubuntu9_i386.deb) ...
  Unpacking replacement gcc-4.8 ...
  Preparing to replace libgcc-4.8-dev:i386 4.8.1-10ubuntu8 (using .../libgcc-4.8-dev_4.8.1-10ubuntu9_i386.deb) ...
  Unpacking replacement libgcc-4.8-dev:i386 ...
  Selecting previously unselected package libgfortran-4.8-dev:i386.
  Unpacking libgfortran-4.8-dev:i386 (from .../libgfortran-4.8-dev_4.8.1-10ubuntu9_i386.deb) ...
  Selecting previously unselected package libc-dev-bin.
  Unpacking libc-dev-bin (from .../libc-dev-bin_2.17-93ubuntu4_i386.deb) ...
  Selecting previously unselected package libc6-dev:i386.
  Unpacking libc6-dev:i386 (from .../libc6-dev_2.17-93ubuntu4_i386.deb) ...
  Selecting previously unselected package gfortran-4.8.
  Unpacking gfortran-4.8 (from .../gfortran-4.8_4.8.1-10ubuntu9_i386.deb) ...
  Selecting previously unselected package gfortran.
  Unpacking gfortran (from .../gfortran_4%3a4.8.1-2ubuntu3_i386.deb) ...
  Processing triggers for man-db ...
  Setting up libquadmath0:i386 (4.8.1-10ubuntu9) ...
  Setting up libitm1:i386 (4.8.1-10ubuntu9) ...
  Setting up libgomp1:i386 (4.8.1-10ubuntu9) ...
  Setting up libgfortran3:i386 (4.8.1-10ubuntu9) ...
  Setting up libatomic1:i386 (4.8.1-10ubuntu9) ...
  Setting up libasan0:i386 (4.8.1-10ubuntu9) ...
  Setting up cpp-4.8 (4.8.1-10ubuntu9) ...
  Setting up libgcc-4.8-dev:i386 (4.8.1-10ubuntu9) ...
  Setting up gcc-4.8 (4.8.1-10ubuntu9) ...
  Setting up libgfortran-4.8-dev:i386 (4.8.1-10ubuntu9) ...
  Setting up libc-dev-bin (2.17-93ubuntu4) ...
  Setting up libc6-dev:i386 (2.17-93ubuntu4) ...
  Setting up gfortran-4.8 (4.8.1-10ubuntu9) ...
  Setting up gfortran (4:4.8.1-2ubuntu3) ...
  update-alternatives: using /usr/bin/gfortran to provide /usr/bin/f95 (f95) in auto mode
  Processing triggers for libc-bin ...
  >

now

  >which gfortran
  /usr/bin/gfortran
  >gfortran -v
  Using built-in specs.
  COLLECT_GCC=gfortran
  COLLECT_LTO_WRAPPER=/usr/lib/gcc/i686-linux-gnu/4.8/lto-wrapper
  Target: i686-linux-gnu
  Configured with: ../src/configure -v --with-pkgversion='Ubuntu/Linaro 4.8.1-10ubuntu9' --with-bugurl=file:///usr/share/doc/gcc-4.8/README.Bugs --enable-languages=c,c++,java,go,d,fortran,objc,obj-c++ --prefix=/usr --program-suffix=-4.8 --enable-shared --enable-linker-build-id --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --with-gxx-include-dir=/usr/include/c++/4.8 --libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu --enable-libstdcxx-debug --enable-libstdcxx-time=yes --enable-gnu-unique-object --enable-plugin --with-system-zlib --disable-browser-plugin --enable-java-awt=gtk --enable-gtk-cairo --with-java-home=/usr/lib/jvm/java-1.5.0-gcj-4.8-i386/jre --enable-java-home --with-jvm-root-dir=/usr/lib/jvm/java-1.5.0-gcj-4.8-i386 --with-jvm-jar-dir=/usr/lib/jvm-exports/java-1.5.0-gcj-4.8-i386 --with-arch-directory=i386 --with-ecj-jar=/usr/share/java/eclipse-ecj.jar --enable-objc-gc --enable-targets=all --enable-multiarch --disable-werror --with-arch-32=i686 --with-multilib-list=m32,m64,mx32 --with-tune=generic --enable-checking=release --build=i686-linux-gnu --host=i686-linux-gnu --target=i686-linux-gnu
  Thread model: posix
  gcc version 4.8.1 (Ubuntu/Linaro 4.8.1-10ubuntu9)

6 my Fortran cheat sheet notes

1.
use this to compile
  gfortran   -fcheck=all -Wall -Wconversion -Wextra -Wconversion-extra -pedantic
2.
  ldd -- shows what libraries a program linked to
  nm  -- shows what symbols in the shared library of object file and type of symbol
  
  reference for the kind  data
  http://docs.oracle.com/cd/E19059-01/stud.10/819-0492/4_f95.html
  
  compile options to use
  gfortran -Wextra -Wall -pedantic -fcheck=all -fcheck=do -fwhole-file
  -fcheck=pointer-O2 -funroll-loops -ftree-vectorize  -Wsurprising
  -Wconversion
  
  I am getting
  >gcc -I/usr/include -c glut_fonts.c
  In file included from /usr/include/features.h:389:0,
                   from /usr/include/inttypes.h:26,
                   from /usr/include/GL/glext.h:5386,
                   from /usr/include/GL/gl.h:2085,
                   from /usr/include/GL/freeglut_std.h:120,
                   from /usr/include/GL/glut.h:17,
                   from glut_fonts.c:1:
  /usr/include/gnu/stubs.h:7:27: fatal error: gnu/stubs-32.h: No such file or directory
  compilation terminated.
  
  I do not know how this happend, but /usr/include/gnu/stubs-32.h was missing.
  So I copied one from different distributions and now it works.
  
  
  To find which file comes from which dep package see
  http://www.debian.org/distrib/packages#search_contents
  
  to find which file comes from which RPM package see
  
  
  static link note
  -------------------
  2.7 Influencing the linking step
  
  These options come into play when the compiler links object
  files into an executable output file. They are meaningless if
  the compiler is not doing a link step.
  
  -static-libgfortran
      On systems that provide libgfortran as a shared and a static
      library, this option forces the use of the static version. If no
      shared version of libgfortran was built when the compiler was
      configured, this option has no effect.
  
  getting link error when doing static
  missing __gxx_personality_v0
3.
to have a loop exit loop type construct
        my_loop: do
           read (7, '(A)') V
           if (V(1) /= "#") exit my_loop
        end do ReadComments
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