Histogram with y-range not specified

Q&A
1

I am trying to make an histogram following the last example of the man page where the y-range is not specified.

gmt histogram errors.xy -T1 -R-10/10/0/0 -Jxc/0.01c -Bx2+lError -By100+lCounts -Gblack -i1 -V -pdf plot

I try it and a lot of different variations (with different data and ranges) but I can’t. It always complain about the -R values. What am I doing wrong?

2

Well, the man page is missing stuff in -J: It says it wil use 0.75cm/m but nothing is specified. So at least it should be -Jx0.75c/0.01c. But the whole example is fantasy, there were never such a data file, and this command was never actually run.
If you leave off -R entirely and do a proper modern command (not the 1-liner) then it may work.

3

Ok. Thanks Paul.

I saw the #4863. So I understand that now (in 6.2 dev) the following should work?

gmt begin Histo png
gmt histogram @v3206_06.txt -T100 -Jx0.002c/1c -Bxaf -By1 -Gblack -Z1 -R-6000/0/0/0
gmt end show

Or should I use this?

gmt begin Histo png
gmt histogram @v3206_06.txt -I -T100 -Z1 > q.txt
Max=$(gmt info q.txt -C -i3 -o1 -I2)
gmt histogram @v3206_06.txt -T100 -JX10/5c -Bxaf -Bya1f -Gblack -Z1 -R-6000/0/0/$Max
gmt end show
4

You could use either I think. If the first one works for you then it will be faster, while the second gives you more options. Let us know if there are ahy other issues!

5

With the first option I get this error:

histogram [ERROR]: Option -R parsing failure. Correct syntax:
	-R<xmin>/<xmax>/<ymin>/<ymax>[/<zmin>/<zmax>]
	  Append +r if giving lower left and upper right coordinates
	-Rg or -Rd for global domain
	-R<grdfile> to take the domain from a grid file
histogram [ERROR]: Offending option -R-6000/0/0/0
6

I get the same as you. Worked for a case like in the documentation but I did not test much. Will have a look. Works without -R.

7

Thanks Paul. Now it works.

8

Just an idea that maybe could be add and maybe it is not difficult to implement. I don’t really need it.

Let that this could also work with a log scale.

gmt begin Histo png
gmt histogram @v3206_06.txt -T100 -Jx0.002c/1c**l** -Bxaf -By1 -Gblack -Z1 -R-6000/0/0/0
gmt end show

Now I get:

histogram [INFORMATION]: Use w/e/s/n = -6000/0/0/11 and x-tick/y-tick = 0/1
histogram [ERROR]: Option -JX|x:  Limits must be positive for log10 option
histogram [ERROR]: General map projection error