Re: Adding c functions into gnuplot

[Lutz M. <lut...@gm...>]

On Monday 07 July 2008 15:59:13 emilio wrote:
> I need to use some functions of the GSL library (Jacobi functions) as a
> builtin function of gnuplot.

Here is a workaround: write a simple C program that takes a single command 
line argument x, calculates the function value and writes it to stdout. 
Let's say this program is called jacobi, then you can define the function

  jacobi(x)=0+system(sprintf("jacobi %f",x))

inside gnuplot, which you can use like any other function (from what I 
remember the "0+" notation is necessary to force the conversion from a 
string to a number). It is very slow, though.

It would be nice if the GSL functions were available natively, but there 
seem to license issues (see feature request 968727 on SourceForge).

Hope this helps,

  Lutz