Re: [boost] Producing graphs for documentation

From: Janek Kozicki (janek_listy_at_[hidden])
Date: 2007-01-08 14:59:16

Kevin Lynch said:     (by the date of Mon, 08 Jan 2007 13:53:04 -0500)

> You could look into gnuplot.  It's output leaves something to be desired 
> for printed publications, but for online or documentation plots it's not 
> bad. 

not correct. I'm using gnuplot for all my publications in journals,
and the quality of graphs is impressive. You just need to fiddle a
bit with few options:

- if you use .ps output format you get TeX style math formula
  capabilities in labels

- pick some nice font

- setting xrange, yrange, titles, xlabel, xlabel.

- label placement too, an additional argument after label string can
displace the label a bit up or left if it feels 'out of place' and
you think that the aligmnment can be better.

- setting grid or not

- with multiplot you can make several plots in single picture, very
useful when I wanted a "top" view in color, and a "cross-section" on
the left of 3D data (like topographic map).

I have written several programs, that after finishing calculations
just dump columns of numbers to file. And one of them even writes a
gnuplot script that plots that data, like:

plot 'file.dat' using ($1/100):(sin($2)) with lines

The best is that scripts allow to make it fully automated. A more
sophisticated script only has some variables at the top with comments
what they do mean. And the user only changes their values to get the
right plot.

check that one:

set terminal postscript portrait enhanced mono lw 1 "Helvetica" 11
set out 'plot.ps'
scale=0.7
set size scale, 0.5*scale
set ylabel "{/Symbol D}d" 2
set xlabel "{/Symbol D}L"
py=-0.055*scale

d=1
L=10
v=0.3

set title "Change of rod diameter {/Symbol D}d assuming d=1, L=10, {/Symbol u}=0.3"

  plot -d*v*(x/5)          title "{/Symbol D}d = - d {/Symbol u}
{{/Symbol D}L/L}" \ , -d*(1-(1+(x/5))**(-v)) title "{/Symbol D}d = -
d (1-(1+{{/Symbol D}L/L} )^{-{/Symbol u}})"

-- 
Janek Kozicki                                                         |