Provided by: grass-doc_7.4.0-1_all 
NAME
d.linegraph - Generates and displays simple line graphs in the active graphics monitor display frame.
KEYWORDS
display, cartography
SYNOPSIS
d.linegraph
d.linegraph --help
d.linegraph [-xysl] x_file=string y_file=string[,string,...] [directory=string]
[y_color=string[,string,...]] [color_table=style] [width=integer[,integer,...]]
[title_color=string] [x_title=string] [y_title=string] [title=string] [y_range=min,max]
[y_tics=float[,float,...]] [x_scale=float] [y_scale=float] [icon=string] [point_size=float]
[secondary_color=name] [secondary_width=integer[,integer,...]] [--help] [--verbose] [--quiet]
[--ui]
Flags:
-x
Scale only X labels, not values
-y
Scale only Y labels, not values
-s
Draw points
-l
Do not draw lines
--help
Print usage summary
--verbose
Verbose module output
--quiet
Quiet module output
--ui
Force launching GUI dialog
Parameters:
x_file=string [required]
Name of data file for X axis of graph
y_file=string[,string,...] [required]
Name of data file(s) for Y axis of graph
directory=string
Path to files
Path to the directory where the input files are located
y_color=string[,string,...]
Color for Y data
color_table=style
Name of color table
Options: aspect, aspectcolr, bcyr, bgyr, blues, byg, byr, celsius, corine, curvature, differences,
elevation, etopo2, evi, fahrenheit, gdd, grass, greens, grey, grey.eq, grey.log, grey1.0, grey255,
gyr, haxby, kelvin, ndvi, ndwi, oranges, population, population_dens, precipitation,
precipitation_daily, precipitation_monthly, rainbow, ramp, random, reds, roygbiv, rstcurv, ryb, ryg,
sepia, slope, soilmoisture, srtm, srtm_plus, terrain, viridis, water, wave
aspect: aspect oriented grey colors
aspectcolr: aspect oriented rainbow colors
bcyr: blue through cyan through yellow to red
bgyr: blue through green through yellow to red
blues: white to blue
byg: blue through yellow to green
byr: blue through yellow to red
celsius: blue to red for degree Celsius temperature
corine: EU Corine land cover colors
curvature: for terrain curvatures (from v.surf.rst and r.slope.aspect)
differences: differences oriented colors
elevation: maps relative ranges of raster values to elevation color ramp
etopo2: colors for ETOPO2 worldwide bathymetry/topography
evi: enhanced vegetative index colors
fahrenheit: blue to red for Fahrenheit temperature
gdd: accumulated growing degree days
grass: GRASS GIS green (perceptually uniform)
greens: white to green
grey: grey scale
grey.eq: histogram-equalized grey scale
grey.log: histogram logarithmic transformed grey scale
grey1.0: grey scale for raster values between 0.0-1.0
grey255: grey scale for raster values between 0-255
gyr: green through yellow to red
haxby: relative colors for bathymetry or topography
kelvin: blue to red for temperature in Kelvin scale
ndvi: Normalized Difference Vegetation Index colors
ndwi: Normalized Difference Water Index colors
oranges: white to orange
population: color table covering human population classification breaks
population_dens: color table covering human population density classification breaks
precipitation: precipitation color table (0..2000mm)
precipitation_daily: precipitation color table (0..1000mm)
precipitation_monthly: precipitation color table (0..1000mm)
rainbow: rainbow color table
ramp: color ramp
random: random color table
reds: white to red
roygbiv: no description
rstcurv: terrain curvature (from r.resamp.rst)
ryb: red through yellow to blue
ryg: red through yellow to green
sepia: yellowish-brown through to white
slope: r.slope.aspect-type slope colors for raster values 0-90
soilmoisture: soilmoisture color table (0.0-1.0)
srtm: color palette for Shuttle Radar Topography Mission elevation
srtm_plus: color palette for Shuttle Radar Topography Mission elevation (with seafloor colors)
terrain: global elevation color table covering -11000 to +8850m
viridis: perceptually uniform sequential color table viridis
water: water depth
wave: color wave
width=integer[,integer,...]
Width of the lines
title_color=string
Color for axis, tics, numbers, and title
Default: black
x_title=string
Title for X data
Default:
y_title=string
Title for Y data
Default:
title=string
Title for Graph
Default:
y_range=min,max
Minimum and maximun value for Y axis (min,max)
y_tics=float[,float,...]
Tic values for the Y axis
x_scale=float
Scale for X values
y_scale=float
Scale for Y values
icon=string
Symbol for point
Options: basic/arrow, basic/arrow1, basic/arrow2, basic/arrow3, basic/box, basic/circle,
basic/cross1, basic/cross2, basic/cross3, basic/diamond, basic/hexagon, basic/marker, basic/octagon,
basic/pin, basic/pin_dot, basic/point, basic/pushpin, basic/star, basic/triangle, basic/x,
demo/muchomurka, demo/smrk, extra/4pt_star, extra/adcp, extra/airport, extra/alpha_flag,
extra/bridge, extra/dim_arrow, extra/dive_flag, extra/fiducial, extra/fish, extra/half-box,
extra/half-circle, extra/offbox_ne, extra/offbox_nw, extra/offbox_se, extra/offbox_sw,
extra/pentagon, extra/ping, extra/ring, extra/simple_zia, extra/target, geology/circle_cross,
geology/half-arrow_left, geology/half-arrow_right, geology/strike_box, geology/strike_circle,
geology/strike_cleavage, geology/strike_half-bowtie, geology/strike_line, geology/strike_parallel,
geology/strike_triangle, legend/area, legend/area_curved, legend/line, legend/line_crooked,
n_arrows/basic_compass, n_arrows/fancy_compass, n_arrows/n_arrow1a, n_arrows/n_arrow1b,
n_arrows/n_arrow2, n_arrows/n_arrow3, n_arrows/n_arrow4, n_arrows/n_arrow5, n_arrows/n_arrow6,
n_arrows/n_arrow7a, n_arrows/n_arrow7b, n_arrows/n_arrow8a, n_arrows/n_arrow8b, n_arrows/n_arrow9
Default: basic/circle
point_size=float
Point size
Default: 5
secondary_color=name
Color
Color for point symbol edge color
Default: black
secondary_width=integer[,integer,...]
Width of point symbol lines
Default: 0.1
DESCRIPTION
d.linegraph is a module to draw simple x,y line graphs (plots) based on numerical data contained in
separate files.
Data format
The X and Y data files for the graph are essentially a column of numbers in each file, with one input
number per line. The program expects that each X value will have a corresponding Y value, therefore the
number of lines in each data input file should be the same. Essentially, the X data becomes the X axis
reference to which the Y data is plotted as a line. Therefore, the X data should be a monotonically
increasing progression of numbers (i.e. "1,2,3,..."; "0, 10, 100, 1000,..."; "...-5,-1,0,1,5..."). If
multiple Y data files are used, the Y axis scale will be based on the range of minimum and maximum values
from all Y files, then all Y data given will be graphed according to that Y scale. Therefore, if multiple
Y data inputs are used with dissimilar units, the graph produced comparing the two will be deceptive.
File inputs
If the directory option is provided, the paths to files can (and should) be only relative paths to these
files. While this is not recommended for scripting, it can be advantageous when typing the paths
manually. For example when all files are stored in the directory /home/john/data, the user can provide
the following in the command line:
d.linegraph directory=/home/john/data x_file=x.txt y_file=y1.txt,y2.txt
Managing colors
The user can specify the y_color option, the color_table option or just leave the defaults to influence
the color of the plotted lines.
Colors specified by y_color option are used for drawing the lines in the graph. If multiple Y data files
are used, an equal number of colors may be used to control the colors of the lines. Colors will be
assigned to Y data in respect to the sequence of instantiation on the command line. It can be one of
GRASS GIS named colors or the RGB values from 0-255 separated by colons (RRR:GGG:BBB).
Alternatively, the user can use the color_table option to specify one of the GRASS GIS predefined color
tables.
By default, a series of colors will be chosen by the module if none are provided upon invocation. The
order of default colors is red, green, violet, blue, orange, gray, brown, magenta, white, and indigo. The
user is advised not to rely on the order of default colors but to either use the y_color or the
color_table option to obtain predictable and reproducible results.
The color to be used for titles, axis lines, tics, and scale numbers is determined by the title_color
option. The user can provide one of the GRASS GIS named colors (such as gray, white, or black) or use the
GRASS GIS colon-separated format for RGB (RRR:GGG:BBB).
Titles, labels, and tics
The title option specifies the text for the title of the graph. It will be centered over the top of
graph. The x_title option is a text to describe data for X axis. It will be centered beneath the graph.
Default is no text unless there is a need for a unit descriptor determined by the d.linegraph module,
then string such as "in hundreds" is generated. The y_title option is a text to describe data for Y
axis. It will be centered beneath the X data description. Similarly, to the x_title option, default is no
text unless there is a need for an auto-generated description. In the case of graphs with multiple lines
(multiple inputs for Y axis), user may wish to use more specific text placement using the d.text or
v.label programs.
NOTES
For historical reasons, the d.linegraph module accepts titles of more than one word where the underscore
character ("_") is used to represent spaces (" "). For example "Census_data_1990" would be printed over
the graph as "Census data 1990". The use of underscores is not necessary to use as long as the parameter
is quoted in the command line. In general, use of underscores is not recommended and there is no need to
use it at all in the GUI or when using d.linegraph in Python scripts.
The way the program locates and labels tic marks is less than perfect:
1) although distances between Y tics are proportional to the value, they are not proportional on the X
axis;
2) decimal values between -1 and 1 can be printed on the X axis, but not on Y. (With respect to the
later, the input for Y values can all be multiplied by a factor of 10 before graphing).
Depending on the user’s needs, it might be easier or more appropriate to use a 3rd party tool such as
xgraph, gnuplot, Matplotlib in Python, or R instead of d.linegraph. For a more general solution for
plotting in GRASS GIS, the user is advised to use the d.graph module.
EXAMPLE
The following can be executed in Bash to create the input data for this example. The user can just create
these files in a text editor, save them and specify path to them.
cat > x.txt <<EOF
1
3
4
6
9
EOF
cat > y1.txt <<EOF
50
58
65
34
27
EOF
cat > y2.txt <<EOF
10
20
35
50
45
EOF
The next command sequence creates a file plot.png in the current directory which is the drawing made by
d.linegraph.
d.mon start=cairo output=plot.png width=400 height=400
d.linegraph x_file=x.txt y_file=y1.txt,y2.txt
d.mon stop=cairo
SEE ALSO
d.frame, d.text, v.label, d.graph, d.histogram
AUTHOR
Chris Rewerts, Agricultural Engineering, Purdue University
Last changed: $Date: 2017-02-02 10:10:41 +0100 (Thu, 02 Feb 2017) $
SOURCE CODE
Available at: d.linegraph source code (history)
Main index | Display index | Topics index | Keywords index | Graphical index | Full index
© 2003-2018 GRASS Development Team, GRASS GIS 7.4.0 Reference Manual
GRASS 7.4.0 d.linegraph(1grass)