Click for printer friendely version of this HowTo Numerical Experiments One of the easiest ways to explore a model is to simply make numerical experiments. These experiments can be as simple as plotting the model response as a function of the independent variable(s). Over the years we have accumulated a toolbox filled with a number of useful command-line tools for performing these experiments. The toolbox is available as a tgz file (analyze.tgz) for use on any system with a C compiler. A simple example of these tools in action is is shell> series 0 10 .1 | \ > tf x1 2.5*exp(-3.5*x1) | xmgrace -pipe The first part of the pipe generates the independent variable values, the second component transforms the independent variable into the model function, in this case, an exponential. The third component plots the data using grace (or the graphing program of your choice). If the model is not an algebraic model, but rather described by the solution to an ordinary or partial differential equation, then often a simple Euler integration and its graph is adequate to give a general idea of what the model is doing. The Section 2.4 gives an overview of this and other numerical methods. The bottom line is always to plot the results, never simply look at a list of numbers. It is surprising what a graphical representation will reveal that numbers hide. Click for printer friendely version of this HowTo

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