Color Images

An excellent way to display a function of two variables, $f(x,y)$, is to form a color image whereby the color of each pixel corresponds to the value of $f(x,y)$ at that location. The tool to accomplish this must translate the function range to a color palette range. For our purpose, this tool must read in a 2-dimensional array containing the values of $f(x,y)$ on a 2-dimensional lattice and produce the color image. The python script plot_image.py does precisely this. It is based on the matplotlib.

matplotlib is a Python 2-dimension plotting library which produces publication quality figures with great flexibility in a variety of formats. The web site describes how to download, install and use this library. The tutorials, user's guide and examples found in this site are easier to read by a reader with some previous knowledge of Python and Numerical Python.

Use gen_data.c gen_data_sharp.c gen_data_rectangle.c to form simple images by feeding sample data in plot_image.py. These codes produce images of size ( $N_x = 200 \times N_y = 200$ ) and ( $N_x = 300 \times N_y = 200$ ) for the third code respectively. Read the comments in plot_image.py to learn how to use it. Practice the different options.