graphics_gnuplot_test
graphics_gnuplot_test,
a FORTRAN90 code which
illustrates how various kinds of data can be displayed and analyzed
graphically, using the gnuplot() graphics package.
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 xaxis. 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 ith 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 computer code and data files described and made available on this web page
are distributed under
the GNU LGPL license.
Languages:
graphics_gnuplot_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,
FORTRAN90 codes which
use dislin(), which
is a scientific graphics package,
by Helmut Michels.
gnuplot_test,
FORTRAN90 codes which
write data and command files
so that gnuplot() can create plots of the results.
Reference:

Philipp Janert,
Gnuplot in Action: Understanding Data with Graphs,
Manning, 2010,
ISBN13: 9781933988398,
LC: QA276.4.J37.
Source code:
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.
corkscrew_plot3d generates (X,Y,Z) points that lie along a 3D curve
looking something like a corkscrew.
The gnuplot() program is used.
grid_surface records, on a 41x41 grid over [2,2]x[2,+2], the
values z = exp((x^2+y^2)) * cos(0.25*x) * sin(y) * cos(2*(x^2+y^2)).
The data is plotted as a surface.
mario_fill makes a simple image of Mario,
by constructing a grid of squares filled with color.
The gnuplot() program is used.
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.
Last modified on 22 July 2020.