Book Image

gnuplot Cookbook

By : Lee Phillips
Book Image

gnuplot Cookbook

By: Lee Phillips

Overview of this book

gnuplot is the world's finest technical plotting software, used by scientists, engineers, and others for many years. It is in constant development and runs on practically every operating system, and can produce output in almost any format. The quality of its 3d plots is unmatched and its ability to be incorporated into computer programs and document preparation systems is excellent. gnuplot Cookbook ñ it will help you master gnuplot. Start using gnuplot immediately to solve your problems in data analysis and presentation. Quickly find a visual example of the graph you want to make and see a complete, working script for producing it. Learn how to use the new features in gnuplot 4.4. Find clearly explained, working examples of using gnuplot with LaTeX and with your own computer programming language. You will master all the ins and outs of gnuplot through gnuplot Cookbook. You will learn to plot basic 2d to complex 3d plots, annotate from simple labels to equations, integrate from simple scripts to full documents and computer progams. You will be taught to annotate graphs with equations and symbols that match the style of the rest of your text, thus creating a seamless, professional document. You will be guided to create a web page with an interactive graph, and add graphical output to your simulation or numerical analysis program. Start using all of gnuplot's simple to complex features to suit your needs, without studying its 200 page manual through this Cookbook.
Table of Contents (18 chapters)
gnuplot Cookbook
About the Author
About the Reviewers
Finding Help and Information

Smoothing your data

As an option to the plot command, gnuplot offers several smoothing functions. The name smooth is a bit misleading. Included in the options for the smooth plotstyle are several ways to process your data that would not most naturally be described as smoothing. We give examples of some of these in the following recipes. In the current recipe we show how to use the smoothing option that seems to be most immediately useful if you have some noisy data and want to draw a qualitatively smooth curve through it, to, as they say, guide the eye.

Getting ready

This recipe uses the datafile rs.dat; make sure that it is in your current directory. This file contains two columns that are the x and y coordinates of a simple sine wave of frequency and amplitude 1 to which normally distributed random data centered on 0 is added; that is, a sine curve plus the type of noise that might arise from actual measurements. In the following figure, we have a plot of the noisy sine wave, plotted with...