**difft** – a symbolic differentiator, current version 0.1.12

Sources: current

The difft utility computes the derivative of a function, optionally printing each differentiation and reduction rule as it does so. It formats its output as LaTeX, a Gnuplot equation, a C file (ANSI C89), or MathML.

difft is a quick, batch-mode derivative calculator without the overhead or complexity of tools
like Sage. It is an ISC-licensed open source

UNIX
utility written in ISO C99, with no compile- or run-time dependencies.

This gallery showcases the results of pipelining difft, LaTeX and dvipng, and Gnuplot.

A sample multivariate trigonometric function is

`echo "(sin(x)*cos(y))" | difft -n -dx,y | latex`

.

Taking the partial derivative with respect to *x* and *y* (for all steps of differentiation: PNG, XHTML) produces

`echo "(sin(x)*cos(y))" | difft -xx,y | latex`

`echo "(sin(x)*cos(y))" | difft -xx,y -Tgnuplot | gnuplot`

The cdf of the Gumbel distribution is

`echo "(e^-(e^-x))" | difft -n -fF | latex`

.

Its pdf (for all steps of differentiation: PNG, XHTML) is thus

`echo "(e^-(e^-x))" | difft -xx,y | latex`

`echo "(e^-(e^-x))" | difft -xx,y -Tgnuplot | gnuplot`

difft(1) | symbolic differentiator |

This utility was developed and is maintained at the Stockholm School of Economics, Department of Economics. Contact Kristaps Dzonsons with bug-reports, questions, comments, patches, and so on.

28-01-2012: version 0.1.12

Lifted signed-integer constraints on number of allocations.
Added **-Tc** output format.
Cleaned up documentation.

Copyright © 2011, 2012 Kristaps Dzonsons, $Date: 2012/01/28 20:45:58 $