graphics_gnuplot_test

graphics_gnuplot_test, a C code which illustrates how data can be displayed and analyzed graphically, using the gnuplot() graphics program.

Some common plot types include:

• animation, a sequential display of images which are meant to suggest motion or evolution.
• bar, a display of values y(1:n) in which every value y(i) is represented by a bar of that height.
• bar3d, a display of values z(1:m,1:n) over a 2D grid, in which every value z(i,j) is represented by a bar of that height.
• barh, a display of values x(1:n) in which every value x(i) is represented by a horizontal bar of that length. The horizontal format can be more suitable for labeling bars when there are many of them.
• between, a line plot of a curve, and a filled plot of the area between the curve and the x-axis. Alternatively, a filled plot of the area between two curves.
• binary_tree, a connected directed graph with no circuits, in which each node has no more than 2 descendants.
• contour fill, a display of values z(x,y) in which the values of z are suggested by regions filled with color.
• contour line, a display of values z(x,y) in which the values of z are suggested by colored contour lines.
• decision_tree, a connected directed graph with no circuits, in which labeled nodes represent current states to be tested, and edges represent the choice or decision to move from one state to another.
• dendrogram, a connected directed graph with no circuits, which generally has a single root node, and illustrates the genealogy or relatedness of a set of objects.
• digraph, a "directed graph", nodes (possibly with defined locations, labels or colors), connected by directed edges (possibly with defined weights, labels, colors or linestyles).
• fill, a shape composed of polygons, each of which is filled with a particular color.
• graph, nodes (possibly with defined locations, labels or colors), connected by undirected edges (possibly with defined weights, labels, colors or linestyles).
• histogram, a display of values x in which the x range is divided into intervals, and the value y(i) represents the number of x values in the i-th interval, and a bar plot of intervals versus count is displayed.
• plot, a display of a single curve defined by a sequence of functional pairs (x,y(x)), or a function y=f(x) sampled over an interval, or a sequence of related pairs (x,y).
• plot3d, a 3D display of a single curve defined by a sequence of triples (x(i),y(i),z(i)), or a parametric function (x(t),y(t),z(t)) sampled over an interval.
• plots, several curves on a single display.
• scatter, a display of unconnected pairs (x,y), whose positions are indicated by markers.
• scatter3d, a 3D display of unconnected triples (x,y,z), whose positions are indicated by markers.
• scatters, a scatter plot involving several distinct sets of (x,y) pairs are displayed, distinguished by markers of different size, shape or color.
• subplots, a display involving two or more separate plots, shown as a single figure.
• surface, a 3D display of values z(x,y), represented as a surface.
• vector, a 2D display of vectors (u,v)(x,y), representing a gradient field, an ODE direction field, or a flow of some kind.

Licensing:

The information on this web page is distributed under the MIT license.

Languages:

graphics_test is available in a C/dislin() version and a C/gnuplot() version and a C++/dislin() version and a C++/gnuplot() version and a Fortran90/dislin() version and a Fortran90/gnuplot() version and a MATLAB version and an Octave version and a Python version and an R version.

Related Data and Programs:

dislin_test, C codes which use dislin(), which is a scientific graphics package, by Helmut Michels.

gnuplot_test, C codes which write data and command files so that the gnuplot() program can create plots of the results.

Reference:

1. Philipp Janert,
   Gnuplot in Action: Understanding Data with Graphs,
   Manning, 2010,
   ISBN13: 978-1-933988-39-8,
   LC: QA276.4.J37.

Source code:

• graphics_gnuplot_test.sh, runs all the tests.

album_bar lists the year, and total number of music albums (LP's, cassettes, CD's and dowloads) sold each year from 2007 to 2017. This data is plotted as a bar graph. The gnuplot() program is used.

• album_data.txt, a data file
• album_bar.c, reads the data and creates the gnuplot command file.
• album_bar.sh, runs the test.
• album_bar.txt, the output file.
• album_commands.txt, the gnuplot() command file.
• album_bar.png, the plot.

automobile_scatter contains prices and weights of cars available in 1985. A scatter plot is to be made. The gnuplot() program is used.

• automobile_data.txt, a data file.
• automobile_scatter.c, reads the data and creates the gnuplot command file.
• automobile_scatter.sh, runs the test.
• automobile_scatter.txt, the output file.
• automobile_commands.txt, the gnuplot() command file.
• automobile_scatter.png, the plot.

brownian_2d_plot plots data representing 1000 steps of Brownian motion in two dimensions. Unlike a typical y=f(x) plot, this data wanders around the page. The gnuplot() program is used.

• brownian_2d_data.txt, the data file.
• brownian_2d_plot.c, plots the data
• brownian_2d_plot.sh, runs the test.
• brownian_2d_plot.txt, the output file.
• brownian_2d_commands.txt, the gnuplot() command file.
• brownian_2d_plot.png, the plot.

bulgaria_plot takes data about the Bulgarian population over time and makes a plot of (time,population). The gnuplot() program is used.

• bulgaria_data.txt, a data file; each line is a year and population count.
• bulgaria_plot.c, creates a gnuplot() command file to plot the data.
• bulgaria_plot.sh, runs the test.
• bulgaria_plot.txt, the output file.
• bulgaria_commands.txt, the gnuplot() command file.
• bulgaria_plot.png, the plot.

caffeine_scatter seeks a relationship between the percentage of blindness due to cataracts, and the daily intake of caffeine, in a number of countries. A scatter plot is produced. The gnuplot() program is used.

• caffeine_data.txt, cataract percentage, and milligrams of caffeine.
• caffeine_scatter.c, creates a gnuplot() command file to plot the data.
• caffeine_scatter.sh, runs the test.
• caffeine_scatter.txt, the output file.
• caffeine_commands.txt, the gnuplot() command file.
• caffeine_scatter.png, the plot.

corkscrew_plot3d generates (X,Y,Z) points that lie along a 3D curve looking something like a corkscrew. The gnuplot() program is used.

• corkscrew_data.txt, the X, Y, Z coordinates.
• corkscrew_plot3d.c, creates the data, and writes the GNUPLOT files.
• corkscrew_plot3d.sh, runs the test.
• corkscrew_plot3d.txt, the output file.
• corkscrew_commands.txt, commands to gnuplot that will create a plot.
• corkscrew_plot3d.png, the plot.

corvette_scatter considers the resale price for Corvettes by model year, displaying the results as a scatter plot. The gnuplot() program is used.

• corvette_data.txt, the data.
• corvette_scatter.c, reads the data and writes the gnuplot command file.
• corvette_scatter.sh, runs the test.
• corvette_scatter.txt, the output file.
• corvette_commands.txt, commands to gnuplot that will create a plot.
• corvette_scatter.png, the plot.

drug_dosage_plots depicts measurements over 48 hours of the blood level concentration of a medicinal drug. The drug needs to reach a certain level to have an effect, but must not exceed the toxic level. A graphic is created which shows, on one plot, the concentration over time, the minimal effective level, and the maximum nonlethal leval. The gnuplot() program is used.

• drug_dosage_data.txt, a data file of times and concentrations;
• drug_dosage_plots.c, reads the data, and plots the concentration level and two limiting straight lines.
• drug_dosage_plots.sh, runs the test.
• drug_dosage_plots.txt, the output file.
• drug_dosage_commands.txt, commands to gnuplot that will create a plot.
• drug_dosage_plots.png, the plot.

geyser_histogram contains the waiting time in minutes between successive eruptions of the Old Faithful geyser. The gnuplot() program is used.

• geyser_data.txt, waiting times and eruption durations.
• geyser_histogram.c, reads the data and writes a gnuplot command file.
• geyser_histogram.sh, runs the test.
• geyser_histogram.txt, the output file.
• geyser_commands.txt, the gnuplot command file.
• geyser_histogram.png, the plot.

geyser_scatter looks for relations between the duration in minutes of the eruption and following waiting times for the Old Faithful geyser. The gnuplot() program is used.

• geyser_data.txt, waiting times and eruption durations.
• geyser_scatter.c, reads the data and writes a gnuplot command file.
• geyser_scatter.sh, runs the test.
• geyser_scatter.txt, the output file.
• geyser_commands.txt, the gnuplot command file.
• geyser_scatter.png, the plot.

insect_scatter3d involves 3 data sets, each containing 10 measurements of 3 quantities for each of 3 species of insect. The quantities are first tarsus width, second tarsus width, and maximum width of the aedeagus. It is of interest to know whether these three measurements are enough to differentiate between members of the three species. A 3D scatter plot is created. The gnuplot() program is used.

• insect_a_data.txt;
• insect_b_data.txt;
• insect_c_data.txt;
• insect_scatter3d.c, reads the data, writes the gnuplot command file.
• insect_scatter3d.sh, runs the test.
• insect_scatter3d.txt, the output file.
• insect_commands.txt, commands to gnuplot that will create a plot.
• insect_scatter3d.png, the plot.

least_squares_plots compares 15 pairs of (x,y) data, the least squares line that approximates their behavior, and a quadratic curve that is much closer to the data. The gnuplot() program is used.

• least_squares1_data.txt, coordinates of the 15 sample points;
• least_squares2_data.txt, coordinates of two points on the least squares approximating line;
• least_squares3_data.txt, coordinates of points on the exact curve;
• least_squares_plots.c, reads the data, writes the gnuplot command file.
• least_squares_plots.sh, runs the test.
• least_squares_plots.txt, the output file.
• least_squares_commands.txt, commands to gnuplot that will create a plot.
• least_squares_plots.png, the plot.

mario_fill makes a simple image of Mario, by constructing a grid of squares filled with color. The gnuplot() program is used.

• mario_fill.c, makes a command file for input to gnuplot.
• mario_fill.sh, runs the test.
• mario_fill.txt, the output file.
• mario_commands.txt, the gnuplot command file.
• mario_fill.png, the plot.

nile_histogram makes a histogram of the yearly measurement of the height of the Nile at maximum flood. By lumping the data into bins, it is easier to see the range of flood heights, and the probability of various values in the range. The gnuplot() program is used.

• nile_data.txt, a list of index and flood height for each year.
• nile_histogram.c, reads the data and writes a gnuplot command file.
• nile_histogram.sh, runs the test.
• nile_histogram.txt, the output file.
• nile_commands.txt, the gnuplot command file.
• nile_histogram.png, the plot.

nile_plot makes a line plot of the yearly measurement of the height of the Nile at maximum flood. The gnuplot() program is used.

• nile_data.txt, a list of index and flood height for each year.
• nile_plot.c, creates a gnuplot() command file to plot the data.
• nile_plot.sh, runs the test.
• nile_plot.txt, the output file.
• nile_commands.txt, the gnuplot() command file.
• nile_plot.png, the plot.

ninety_histogram considers 90 numeric values. We create a histogram, to see how the data spreads out across its range. We spot outliers as histogram bins of low occupancy that are far from the rest of the data. The gnuplot() program is used.

• ninety_data.txt, a text file containing a list of 90 numbers.
• ninety_histogram.c, creates a gnuplot() command file to plot the data.
• ninety_histogram.sh, runs the test.
• ninety_histogram.txt, the output file.
• ninety_commands.txt, the gnuplot() command file.
• ninety_histogram.png, the plot.

predator_plot3d models the populations of predators (foxes) and prey (rabbits) over time. A 3D plot of (time, rabbits, foxes) is created. The gnuplot() program is used.

• predator_data.txt, a list of time, prey, and predator.
• predator_plot3d.c, creates the data, and writes the GNUPLOT files.
• predator_plot3d.sh, runs the test.
• predator_plot3d.txt, the output file.
• predator_commands.txt, commands to gnuplot that will create a plot.
• predator_plot3d.png, the plot.

president_heights_bar plots the heights of US presidents in inches, as a bar plot. The gnuplot() program is used.

• president_heights_data.txt, a data file;
• president_heights_bar.c, creates a gnuplot() command file to plot the data.
• president_heights_bar.sh, runs the test.
• president_heights_bar.txt, the output file.
• president_heights_commands.txt, the gnuplot() command file.
• president_heights_bar.png, the plot.

president_heights_histogram plots the heights of US presidents in inches, as a histogram. By grouping the data by height, we lose the ability to identify specific cases, but we are better able to see the range of heights, and to judge the frequency of various heights. The gnuplot() program is used.

• president_heights_data.csv, a data file;
• president_heights_histogram.c, creates a gnuplot() command file to plot the data.
• president_heights_histogram.sh, runs the test.
• president_heights_histogram.txt, the output file.
• president_heights_commands.txt, the gnuplot() command file.
• president_heights_histogram.png, the plot.

price_plots reads a table of average monthly prices for 11 consumer products, between February 2008 and February 2018, as compiled by the Bureau of Labor Statistics, and plots together the prices of three of the items. The gnuplot() program is used.

• price_data.txt, a data file;
• price_plots.c, creates a gnuplot() command file to plot the data.
• price_plots.sh, runs the test.
• price_plots.txt, the output file.
• price_commands.txt, the gnuplot() command file.
• price_plots.png, the plot.

snowfall_histogram makes a histogram of the yearly snowfall totals at Michigan Tech from 1890 to 2017. The gnuplot() program is used.

• snowfall_data.txt, the data.
• snowfall_histogram.c, creates a gnuplot() command file to plot the data.
• snowfall_histogram.sh, runs the test.
• snowfall_histogram.txt, the output file.
• snowfall_commands.txt, the gnuplot() command file.
• snowfall_histogram.png, the plot.

snowfall_plot makes a line plot of the snowfall at Michigan Tech from 1890 to 2017. The gnuplot() program is used.

• snowfall_data.txt, the data.
• snowfall_plot.c, creates a gnuplot() command file to plot the data.
• snowfall_plot.sh, runs the test.
• snowfall_plot.txt, the output file.
• snowfall_commands.txt, the gnuplot() command file.
• snowfall_plot.png, the plot.

temperature_scatter shows locations in the US where the January temperature was recorded. The gnuplot() program is used.

• temperature_data.txt, January temperature, -longitude, latitude.
• temperature_scatter.c, creates a gnuplot() command file to plot the data.
• temperature_scatter.sh, runs the test.
• temperature_scatter.txt, the output file.
• temperature_commands.txt, the gnuplot() command file.
• temperature_scatter.png, the plot.

temperature_scatter3d shows temperatures and locations in the US where the January temperature was recorded. The gnuplot() program is used.

• temperature_data.txt, the data file, containing temperature, -longitude and latitude.
• temperature_scatter3d.c, creates a gnuplot() command file to plot the data.
• temperature_scatter3d.sh, runs the test.
• temperature_scatter3d.txt, the output file.
• temperature_commands.txt, the gnuplot() command file.
• temperature_scatter3d.png, the plot.

track_bar considers an eye-tracking experiment in which the eye was focused on different regions for different durations. Each region has a text label. A bar graph is desired, in which the bar for each duration is given the appropriate label. The gnuplot() program is used.

• track2_data.txt, a data file including a region name, and a duration;
• track_bar.c, creates a gnuplot() command file to plot the data.
• track_bar.sh, runs the test.
• track_bar.txt, the output file.
• track_commands.txt, the gnuplot() command file.
• track_bar.png, the plot.