Conversion of FORTRAN90 to FORTRAN77
is a FORTRAN90 program which
assists in the conversion of a FORTRAN90 source code file to the
Only a few modifications are made; the user will surely have to go
into the file and make further modifications by hand. The changes
made by the program include:
Input lines recognized as comments will be output with a
first character of "c".
Noncomment input lines which begin in column 1 or 2 will be
indented to start in column 6.
Other noncomment input lines will be indented 4 extra spaces.
Noncomment output lines will automatically be broken into
segments that are no more than 72 characters long, with
excess information continued on the next line.
f90_to_f77 input.f90 output.f
input.f90 is the input FORTRAN90 file;
output.f is the output file, which has been converted.
The computer code and data files made available on this
web page are distributed under
the GNU LGPL license.
F90_TO_F77 is available in
a FORTRAN90 version.
Related Data and Programs:
a FORTRAN90 program which
converts a FORTRAN77 file to FORTRAN90 format,
by Michael Metcalfe;
Examples and Tests:
a sample FORTRAN90 file.
the resulting FORTRAN77 file.
List of Routines:
MAIN is the main program for F90_TO_F77.
HANDLE copies an F90 file making an F77 version.
GET_UNIT returns a free FORTRAN unit number.
S_TAB_BLANKS replaces TAB characters by 6 spaces.
TIMESTAMP prints the current YMDHMS date as a time stamp.
You can go up one level to
the FORTRAN90 source codes.
Last revised on 25 June 2013.