Downloads SWAP

The computer program SWAP

Swap3.2 is free software. When you proceed to the download page, you will have to register before you can download the programme.

Your registration will only be used to maintain an overview of model use.

Download Swap32 (setup file of 6.2 Mb)

After registration and installation (unzip file you should have:

  • an executable version of the SWAP model (tested on MS-Windows-7)
  • examples
  • source code
  • user manual

For more info see the file 'readme_3.2.txt' which comes with the installation set.

The program is supplied without Graphical User Interface. We try to give support to users, but have limited financial sources. Please contact us (Swap-team) if you have any suggestions.

Updated documents of manual and testcases can be found using the hyperlinks on the right.

The Fortran library TTUTIL

The model SWAP uses the Fortran library TTUTIL for input from files.

The Fortran library TTUTIL is a collection of subprograms dealing with often returning problems like input from file, output to file, character string handling, string decoding, file name and unit number handling, date/ time handling and more. The latest versions of the library are being maintained by dr. C. Rappoldt (


D.W.G. van Kraalingen & C. Rappoldt. 2000. Reference manual of the FORTRAN utility library v. 4. Report 5. Plant Research International, Wageningen, The Netherlands.