Fortran flow charts

Visustin generates flow charts from code written in Fortran 66, 77, 90 and 95. It supports standard Fortran and certain additions. We have also added support for many constructs included in Fortran 2003.

Supported Fortran statements

The following statements are supported.

All other statements appear as regular statements without special handling.

Fixed and free form

Both the fixed form (columns 7-72) and the free form code are supported. In the fixed form, columns 1-6 contain line labels, comment marks and line continuation marks, while columns 7-72 contain the actual code. In the free form the code can be in any column. If your code doesn't seem to render well, please check the format setting first. If you have selected the wrong format, the flow chart will appear incorrect.

When the fixed form is selected, you will see a ruler displaying the expected column format, and source code appears in a fixed-width font.

Conditional compilation support

Visustin supports two types of conditional compilation directives: CoCo style conditional compilation (??IF..THEN..??ELSEIF..??ELSE..??ENDIF, Fortran 95 standard) and conventional preprocessors (#if..#endif).

Preprocessor support. Visustin supports both Fortran preprocessor (fpp) and C preprocessor (cpp) directives. The following directives are supported: #if..#elif..#else..#endif, #ifdef, #ifndef. Any line that starts with # is a preprocessor line. The # can exist in any column regardless of whether fixed or free form mode has been selected. C-style preprocessor comments (/*...*/) are not supported. If Visustin does not seem to handle preprocessing code correctly, run your code through your preprocessor first, then flowchart the resulting files with Visustin.

Unsupported Fortran constructs

The following constructs are unsupported.

In fixed form mode, only columns 7-72 are considered. Characters beyond column 72 will be ignored. If your fixed form source contains longer lines, run it through a converter to put it into free form or to shorten the lines.

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