Table of Contents

Copyright

Brief Table of Contents

Table of Contents

Praise for the First Edition

Preface

Acknowledgments

About this Book

1. Getting started

Chapter 1. Prelude: understanding data with gnuplot

1.1. A busy weekend

1.1.1. Planning a marathon

1.1.2. Determining the future

1.2. What is graphical analysis?

1.2.1. Why graphical analysis?

1.2.2. Limitations of graphical analysis

1.3. What is gnuplot?

1.3.1. Gnuplot isn’t GNU

1.3.2. Why gnuplot?

1.3.3. Limitations

1.3.4. Gnuplot 5: the best gnuplot there ever was!

1.4. Summary

Chapter 2. Tutorial: essential gnuplot

2.1. Simple plots

2.1.1. Invoking gnuplot and first plots

2.1.2. Plotting data from a file

2.1.3. Abbreviations and defaults

2.2. Saving commands and exporting graphics

2.2.1. Saving and loading commands

2.2.2. Exporting graphs

2.3. Managing options with set and show

2.4. Getting help

2.5. Summary

Chapter 3. The heart of the matter: the plot command

3.1. Plotting functions and data

3.1.1. Plotting functions

3.1.2. Plotting data

3.2. Math with gnuplot

3.2.1. Mathematical expressions

3.2.2. Built-in functions

3.2.3. User-defined variables and functions

3.2.4. Mathematically undefined values and NaN (not a number)

3.3. Data transformations

3.3.1. Simple data transformations

3.4. Logarithmic plots

3.5. Smooth interpolation and approximation

3.5.1. Interpolation curves

3.5.2. Point distributions

3.5.3. Deduping repeated entries

3.6. Summary

2. Creating graphs

Chapter 4. Managing data sets and files

4.1. Quickstart: the standard data-file format

4.1.1. Comments and header lines

4.1.2. Selecting columns

4.2. Managing structured data sets

4.2.1. Multiple data sets per file: index

4.2.2. Records spanning multiple lines: the every directive

4.3. File format options in detail

4.3.1. Number formats

4.3.2. Comments

4.3.3. Field separator

4.3.4. Missing values

4.3.5. Strings in data files

4.4. Accessing columns and pseudocolumns

4.4.1. Accessing columns by position or name

4.4.2. Pseudocolumns

4.4.3. Column-access functions

4.5. Pseudofiles

4.5.1. Reading data from standard input

4.5.2. Heredocs

4.5.3. Reading data from a subprocess

4.5.4. Writing to a pipe

4.5.5. Generating data

4.6. Metadata in data files

4.7. Other file formats

4.8. Summary

Chapter 5. Practical matters: strings, loops, and history

5.1. Strings

5.1.1. Quotes

5.1.2. String operations

5.1.3. Worked example: plotting the Unix password file

5.2. String expressions and string macros

5.2.1. String expressions in commands

5.2.2. Executing a string with eval

5.2.3. String macros inside commands

5.3. Generating textual output

5.3.1. The print and set print commands

5.3.2. The set table command and the with table style

5.3.3. Reading and writing heredocs

5.4. Simplifying work with inline loops

5.4.1. Loops over numbers

5.4.2. Loops over strings

5.4.3. Summary of inline loops

5.5. Gnuplot’s internal variables

5.6. Inspecting file contents with the stats command

5.6.1. The stats command and internal variables

5.6.2. Further options for the stats command

5.7. Command history

5.7.1. Redrawing a graph

5.7.2. The general history feature

5.7.3. Restoring session defaults

5.8. Summary

Chapter 6. A catalog of styles

6.1. Why use different plot styles?

6.2. Styles and aspects

6.2.1. Choosing styles inline through with

6.2.2. The default sequence

6.2.3. Customizing graph elements

6.3. A catalog of plotting styles

6.3.1. Core styles: lines and points

6.3.2. Indicating uncertainty: styles with error bars or ranges

6.3.3. Styles with steps and boxes

6.3.4. Filled styles

6.3.5. Beyond lines and points: multivariate visualization

6.4. Putting it together

6.5. Other styles

6.6. Summary

Chapter 7. Decorations: labels, arrows, and explanations

7.1. Quick start: minimal context for data

7.2. Understanding layers and locations

7.2.1. Locations

7.2.2. Layers

7.3. Additional graph elements: decorations

7.3.1. Common conventions

7.3.2. Arrows

7.3.3. Text labels

7.3.4. Shapes or objects

7.4. The graph’s legend or key

7.4.1. Turning the key on and off

7.4.2. Placement

7.4.3. Layout

7.4.4. Appearance

7.4.5. Explanations

7.4.6. Default settings

7.5. Worked example: features of a spectrum

7.6. Summary

Chapter 8. All about axes

8.1. Multiple axes

8.1.1. Terminology

8.1.2. Plotting with two coordinate systems

8.1.3. Linking axes

8.2. Selecting plot ranges

8.2.1. What you need to know for interactive work

8.2.2. What you might want to know for batch processing

8.3. Tic marks

8.3.1. Overview and common conventions

8.3.2. Tic mark appearance and placement

8.3.3. Tic labels

8.3.4. Tic mark location and frequency

8.3.5. Reading tic labels from file

8.3.6. Grid and zero axis

8.4. Special case: time series

8.4.1. Turning numbers into names: months and weekdays

8.4.2. General time series: the gory details

8.4.3. Beyond tic labels: processing date/time information

8.5. Summary

3. Mastering technicalities

Chapter

Chapter 9. Color, style, and appearance

9.1. Color

9.1.1. Explicit colors

9.1.2. Alpha shading and transparency

9.1.3. Selecting a color through indexed lookup

9.1.4. Mapping a value into a continuous gradient

9.1.5. Using data-dependent colors

9.1.6. The built-in color sequences

9.1.7. Tips and tricks

9.2. Lines and points

9.2.1. Point types and shapes

9.2.2. Dash pattern

9.3. Customizing color, dash, and point sequences

9.3.1. Customizing line types

9.3.2. Special line types

9.4. Global styles

9.4.1. Data and function styles

9.4.2. Line styles

9.4.3. Arrow styles

9.4.4. Fill styles

9.4.5. Other global styles

9.5. Overall appearance: aspect ratio and borders

9.5.1. Size and aspect ratio

9.5.2. Borders

9.5.3. Margins

9.5.4. Internal variables

9.6. Summary

Chapter 10. Terminals and output formats

10.1. The terminal abstraction

10.1.1. Historical digression

10.1.2. The terminal workflow

10.1.3. Terminal capabilities and the test command

10.2. Font selection and enhanced text mode

10.2.1. Font selection

10.2.2. Font resolution

10.2.3. Enhanced text mode

10.2.4. Worked example

10.3. Generating PNG and PDF with cairo-based terminals

10.4. Using gnuplot with LaTeX

10.4.1. Including a graph in a LaTeX document

10.4.2. Using the cairolatex terminal

10.4.3. Letting LaTeX generate the graph

10.5. Scalable graphics for the Web with SVG and HTML5

10.5.1. The svg terminal

10.5.2. The canvas terminal

10.6. Interactive terminals

10.6.1. Common options

10.6.2. The wxt and qt terminals

10.6.3. The aqua terminal

10.6.4. The windows terminal

10.7. Other terminals

10.8. Summary

Chapter 11. Automation, scripting, and animation

11.1. Loops and conditionals

11.1.1. Worked example: making graph paper

11.1.2. Worked examples: iterating over files

11.1.3. Worked examples: Taylor series and Newton’s method

11.2. Command files

11.2.1. Scripts as subroutines

11.2.2. Worked example: export script

11.3. Batch processing

11.3.1. Using gnuplot in shell pipelines

11.4. Calling gnuplot from other programs

11.4.1. Worked example: calling gnuplot from Perl

11.4.2. Worked example: calling gnuplot from Python

11.4.3. Helpful hints

11.5. Animations

11.5.1. Introducing a delay

11.5.2. Waiting for a user event

11.5.3. Further examples

11.6. Case study: continuously monitoring a live data stream

11.6.1. Using gnuplot to monitor a file

11.6.2. Using a driver to monitor arbitrary data sources

11.7. Summary

Chapter 12. Beyond the defaults: workflow and styles

12.1. The standard interactive workflow

12.1.1. Extracting specifics from command files

12.1.2. Extending the command set

12.1.3. Session variables, loops, and macros

12.2. Using external editors and viewers

12.3. Invoking shell commands from gnuplot

12.3.1. Worked example: plotting each file in a directory

12.4. Hotkeys and mousing

12.4.1. Default hotkeys

12.4.2. Mousing

12.4.3. Custom hotkeys

12.4.4. Capturing mouse events

12.4.5. Case study: placing arrows and labels with the mouse

12.5. Startup configurations and initialization

12.5.1. Startup and initialization files

12.5.2. Environment variables

12.5.3. Gnuplot command-line flags

12.6. Stylesheets

12.6.1. Worked example: stylesheets

12.7. Summary

4. Understanding data

Chapter 13. Basic techniques of graphical analysis

13.1. Representing relationships

13.1.1. Scatter plots

13.1.2. Highlighting trends

13.2. Logarithmic plots

13.2.1. Large variations in data

13.2.2. Power-law behavior

13.3. Point distributions

13.3.1. Summary statistics and box plots

13.3.2. Jitter plots and histograms

13.3.3. Kernel density estimates and rug plots

13.3.4. Cumulative distribution functions

13.4. Ranked data

13.5. Pie charts

13.6. Organizational issues

13.6.1. The lifecycle of a graph

13.6.2. Input data files

13.6.3. Output files

13.7. Presentation graphics

13.8. Summary

Chapter 14. Topics in graphical analysis

14.1. Techniques for time-series plots

14.1.1. Plotting an Apache web server log

14.1.2. Smoothing and differencing

14.1.3. Monitoring and control charts

14.1.4. Changing composition and stacked curves

14.2. Graphical techniques for multivariate data sets

14.2.1. Introduction

14.2.2. Distribution of values by attribute

14.2.3. Distribution by level

14.2.4. Scatter-plot matrix

14.2.5. Parallel-coordinates plot

14.3. Visual perception

14.3.1. Banking

14.3.2. Judging lengths and distances

14.3.3. Plot ranges and whether to always include zero

14.4. Summary

Chapter 15. Coda: understanding data with graphs

Appendix A. Obtaining, building, and installing gnuplot

A.1. Inspecting compile-time options

A.2. Release and development versions

A.3. Installing a prebuilt package

A.3.1. Linux

A.3.2. Mac OS X

A.3.3. Windows

A.4. Building from source

A.4.1. Obtaining the development version from CVS

A.4.2. Layout of the source tree

A.4.3. Building and installing

Appendix B. Resources

B.1. Gnuplot

B.1.1. Websites

B.1.2. Books

B.2. Data repositories

B.3. Books

Appendix C. Surface and contour plots

C.1. Surface plots

C.1.1. The splot command

C.1.2. Special options for surface plots

C.2. View point and coordinate axes

C.2.1. Borders and base plane

C.2.2. View point

C.3. Contour lines and contour plots

C.3.1. Contour plots

C.3.2. Customizing contour lines and their labels

C.4. Plotting data from a file using splot

C.4.1. Grid format

C.4.2. Matrix format

C.5. Smooth surfaces

C.5.1. The set dgrid3d facility

Appendix D. Palettes and false-color plots

D.1. Warm-up examples

D.2. Creating palettes

D.2.1. Color models and components

D.2.2. Defining palettes through nodes

D.2.3. Defining palettes with functions

D.2.4. Displaying and exporting palettes

D.2.5. Some example palettes

D.3. The colorbox

D.3.1. Mapping the plot range to the palette

D.4. Using palettes

D.4.1. Colored surface plots with pm3d

D.5. False-color plots

D.5.1. Using points

D.5.2. Using the pm3d style

D.5.3. Using the image style

D.6. Case study: coloring the Mandelbrot set

D.7. Case study: an interactive palette explorer

D.8. Further reading

Appendix E. Special plots

E.1. Multiplot

E.1.1. Using multiplot mode

E.1.2. Layout options and the set multiplot command

E.1.3. Regular arrays of graphs with layout

E.1.4. Accommodating marginal labels with margins and spacing

E.1.5. Graphs within a graph

E.2. Box-and-whisker plots

E.2.1. Individual box-and-whisker plots

E.2.2. Serial box-and-whisker plots

E.3. Parallel coordinates

E.3.1. Creating parallel-coordinates graphs

E.3.2. Worked example: Iris data, again

E.4. Histograms

Appendix F. Higher math

F.1. Parametric plots

F.2. Non-Cartesian coordinates

F.2.1. Polar coordinates

F.2.2. Cylindrical and spherical coordinates

F.3. Vector fields

F.3.1. Plane vector fields with plot

F.3.2. Three-dimensional vectors with splot

F.4. Built-in mathematical functions

F.5. Complex numbers

F.5.1. Application: Mandelbrot set (pure gnuplot)

F.6. Probability plots

F.6.1. Adding a probability scale

F.7. Curve fitting

F.7.1. Background

F.7.2. A worked example

F.7.3. Using the fit command

F.7.4. Practical advice

F.7.5. Options for the fit command

Index

List of Figures

List of Tables

List of Listings