Solv95 C/C++ & Windows based Delay Differential Equation Solver

This page contains downloadable C files for a graphical user interface windows 9*/NT delay differential equation solver, based on an adaptively stepped embedded RK2(3) scheme with cubic hermite interpolation of lagged variables. The program can be used to integrate systems of ordinary or delay differential equations (and you can also specify discontinuous changes in state variables). There are now a couple of very good ports/extensions:

To use the program you will need to produce a model definition file in C, which is best done by editing a standard template file. You then compile and link your template file along with the other source files supplied in the package. To do this you need a C or C++ compiler: gcc ported to Windows works fine and can be obtained for free (see below). I've also used Borland and Microsoft compilers without problems.

The code is provided under the following conditions: If you do not accept these conditions then do not download the code.
You will need a 486 or higher PC running some flavour of Windows 95/7/8+ or NT and a C/C++ Compiler capable of producing 32-bit GUI executables for Windows 9*/NT. I used Borland C/C++ 5.01, and have tried out microsoft Visual C++ 5 as well. If you don't have a compiler then I can recommend this (free) port of gcc and a site devoted to gcc for Windows .
The following zipped file contains the source code for Solv95, 3 example template files (with compiled versions) and documentation as a latex file and postscript file: Having downloaded and unzipped the programs, print out or view the documentation (manual.tex or This explains how to use the package and describes the models coded in the three examples. If you want to know what the program does before investing the effort in learning how to use it, start by running one or all of the three pre-compiled example models. (I have yet to have a virus problem, but in any case all files were virus checked with an up to date checker before posting. As usual this doesn't constitute a guarantee.)

Bug fixes

Simon N. Wood 14/12/99
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