A dynamic Postscript to generate a different random walk every time you open the document...
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psrw/psrw.ps

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%% 13331
%%
%% Visualise a different 2D random walk every time the file is
%% opened
%%
%% (c) 2018 Vincenzo (KatolaZ) Nicosia <katolaz@freaknet.org>
%%
%% Use and distribute under the terms of the GNU General Public Licence
%% Version 3 or, at your option, any later version.
%%
/myname (./psrw.ps) def
/rwstartx 250 def
/rwstarty 400 def
/rwlength 500 def
/rwstep 8 def
/myreadlines {
dup
255 string
readline
{ 2 -1 roll myreadlines} {pop exit} ifelse
} def
/myloadfile {
(r) file
{myreadlines} loop
closefile
} def
/mywritelines{
count
1 ne
{
dup
count -1 roll
writestring
dup
(\n) writestring
mywritelines
}
{exit} ifelse
} def
/mywritefile {
(w) file
{mywritelines} loop
closefile
} def
/replacefirst {
count -1 roll
pop
count 1 roll
} def
/get_seed {
myname (r) file
dup
255 string
readline
pop
(%% ) anchorsearch
{pop cvi} {pop 201} ifelse
exch closefile
} def
%% This comes from GNU Ghostscript
/concatstrings % (a) (b) -> (ab)
{ exch dup length
2 index length add string
dup dup 4 2 roll copy length
4 -1 roll putinterval
} bind def
/rndangle { rand 360 mod 2 -1 roll pop } def
/newrndpoint {
rndangle
dup
cos rwstep mul
2 -1 roll
sin rwstep mul
} def
erasepage
newpath
rwstartx rwstarty moveto
2 setlinewidth
get_seed
srand
1 1 rwlength { newrndpoint rlineto } for
stroke
myname myloadfile
(%% ) rand 30 string cvs concatstrings
replacefirst
myname mywritefile