GMTXY - XY plot using GMT

The GMTXY script enables the user to make XY-plots with GMT, and can easily 
be adjusted to a preferred layout. The script is written by Matthias Ohrnberger 
and Eirik Tvedt. The input file for GMTXY contains the settings and the XY-data for 
the diagram to be plotted, and is easily adjusted by the user.

Last update August 2004 by Eirik

In order to run on your system, set GMTHOME variable in 3. line of script.
 
Below is an example of an outputfile from the SPEC program.

# OFILENAME   spec_ave_LE-L2S__N_LE-L2S__Z.gmt.ps
# MAINTITLE    Av. of relative spectra w/st. dev. for LE-L2S  N
# MAIN_FONT_SIZE                18 
# MAIN_FONT_TYPE Times-Roman 
# give title, size and switch on or off (1 or 0) the log-scaling of the x-axis.
# XTITLE      Frequency (Hz)                                                    
# XSIZE          12 
# XLOG            1 
# YTITLE      Relative amplitude 
# YSIZE          10 
# YLOG            1 
# GRID_X		1
# GRID_Y		1
# NTRACES                        3 
# BAR_WIDTH		1.0
# LEGEND                         1 
# TRACETITLE   First line 
# TRACECOLOR  black 
# TRACESYMBOL  t
# SYMBOL_SIZE                 0.60 
# LINE_WIDTH                     5 
# LINESTYLE   solid 
# MINX                  0.12207032 
# MAXX                 19.99511719
# MINY                  0.53115237
# MAXY                  1.11497903 
    0.122070   0.563863
    0.146484   0.565051
    0.170898   0.568624
...
(XY-data for the different curves follow)

This file is used as an input for the GMTXY program, with this command line:
gmtxy  spec_all.out

Below is an explanation of the inputfile. These parameters can be changed by 
the user before running the GMTXY, to obtain the preferred result.

# OFILENAME   spec_ave_LE-L2S__N_LE-L2S__Z.gmt.ps
Gives the name of the outputfile, which is a postscript-file. 
# MAINTITLE    Av. of relative spectra w/st. dev. for LE-L2S  N
Gives the title to be printed above the XY-plot. Nothing is printed 
if no title is given. Nordic, German or Spanish characters are not recognized.
# MAIN_FONT_SIZE  18      
Gives the fontsize of the maintitle. (Minimum value is 14.) The fontsizes 
of the annotation and the X- and Y-title is calculated from this fontsize.
# MAIN_FONT_TYPE Times-Roman 
Font-type of the titles and annotations. Several options are available: 
Times-Roman, Times-Bold, Courier, Helvetica-Bold and Bookman-Demi 
(more options are given in the gmtdefaults manual).
# XTITLE      Frequency (Hz)  
Title of the X-axis
# XSIZE  12 
Length of the diagram in cm. Annotations and titles not included.
# XLOG    1 
Linear (0) or logarithmic (1) scale of the X-axis.
# YTITLE      Relative amplitude 
# YSIZE          10 
# YLOG            1
As for X.
# GRID_X		1
# GRID_Y		1
Plot gridlines (1) or not (0), vertical (GRID_X ) and horizontally (GRID_Y ).
# NTRACES  3
Indicates the number of traces to be plotted.
# BAR_WIDTH  1.0
This option is only used when plotting histograms (TRACESYMBOL b), 
and may be left out when plotting curves. The width of the bars is given, 
and the same unit as the X-axis is used. That is, if bar-width is set to 1.0, 
there should be no space between the bars. However, if plotting catstat outputfiles, 
with months as input, the bar-width should be approx. 0.08, with days as input, 
the unit should be 0.0025, to get no space between the bars.  
If TRACECOLOR is white, the bars is not filled. 
# LEGEND   1 
This option does not support histogram plotting (TRACESYMBOL b). Indicate 
if legend should be plotted (1) or not (0). If 1, the colours and/or the symbols 
of the different curves will be given to the right of the diagram together with 
the titles of each curve. If the titles are too long, the text will be cut by the 
rigth margin (can be avoided by reducing MAIN_FONT_SIZE ).

The following parameters are repeated for every dataset to be plotted: 
# TRACETITLE    First line
Title of trace.
# TRACECOLOR  black
Color of trace and/or symbol.  Several options are available, such as 
black, red, blue, yellow, green, pink, purple, brown, orange, cyan, white. 
(for a complete list, give "showrgb" in the command line. Only those colours 
written in one word may be used. Some long names are also not recognized)
# TRACESYMBOL t
Symbol of trace. Options: t (triangle), c (circle), d (diamond), x (cross), 
p (point) or a (star). Append b for plotting histograms. Blank means no symbol. 
(crosses and points are only plotted in black, points also has a fixed size)
# SYMBOL_SIZE    0.60 
Size of symbol (the diameter in cm.)
# LINE_WIDTH  5  
Width of the line. Range 1-20.
# LINESTYLE   solid 
Linestyle. Options: solid, dashed, dotted. No line if blank.
# MINX                  0.12207032
# MAXX                 19.99511719
# MINY                  0.53115237 
# MAXY                  1.11497903 
The maximum and minimum values of the data to be plotted are given here. 
Also, these datas are used to set the range of the X- and Y-axis.
 
Known bugs:
If plotting histograms together with curves, the dataset to be plotted with 
bars should be presented first.