Plotting points with different intensities
Jennifer Gogarten
I have a file of tab delimited data which has the x-coordinate, the
y-coordinate and then the desired intensity of the datapoint (between
0 and 1). How do I incorporate this last bit of information?
So far, I have:
plot "mydatafile" with points pointtype 6 pointsize .5;
This generates points of the desired shape and size at the desired
location. However, I need help as to how to include the intensity of
the points, such that points with an intensity of 1 are the darkest
and points with an intensity getting closer to 0 get progressively
lighter.
Thank you for your help!
Jennifer Gogarten
Jennifer Morris Gogarten
> set view map # 2D plot with Z value encoding color
> set palette gray # grayscale color mapping
None of this appears to be accepted as valid syntax by gnuplot. I think
I'm doing something wrong!
Here's the full .p file, if it helps:
set terminal postscript landscape color 14;
set out "temp.ps";
set multiplot;
set nokey;
set ylabel 'my favorite axis';
set xlabel 'my other favorite axis';
set title 'This is my plot!';
set size 0.7,1;
set xr [0:200];
set yr [0:200];
plot "mydata" with points pointtype 6 pointsize .5;
set nomultiplot;
Also, perhaps it is prudent to mention that I have gnuplot 3.7 installed
on my server, not 4.0?
Thank you very much for your help!
Jennifer Gogarten
Hans-Bernhard Broeker
> > set datafile separator "\t" # tab-separated data
> > set view map # 2D plot with Z value encoding color
> > set palette gray # grayscale color mapping
> None of this appears to be accepted as valid syntax by gnuplot. I think
> I'm doing something wrong!
Not really:
> Also, perhaps it is prudent to mention that I have gnuplot 3.7 installed
> on my server, not 4.0?
That's exactly your problem.
--
Hans-Bernhard Broeker (bro...@physik.rwth-aachen.de)
Even if all the snow were burnt, ashes would remain.
Jennifer Morris Gogarten
> set view map # 2D plot with Z value encoding color
> set palette gray # grayscale color mapping
>
> plot "data" using 1:2:3 with points pt 6 ps .5 palette
Having updated gnuplot, this last line of your suggestion is giving the
error "Too many using specs for this style".
Thoughts?
Thanks for your help!
Jennifer Gogarten
Ethan Merritt
>> set view map # 2D plot with Z value encoding color
>> set palette gray # grayscale color mapping
>> set zrange [0:1] # force full range of color scale
>>
>> plot "data" using 1:2:3 with points pt 6 ps .5 palette
>
>Having updated gnuplot, this last line of your suggestion is giving the
>error "Too many using specs for this style".
Sorry. That should have been "splot" rather than "plot".
--
Ethan A Merritt
Guido Krueger
Hello, I have the same problem. With splot I can plot the points with
different intensities, but if I change the pointsize, the points move
to another position!
With increasing pointsize the hole grid of points is moving to the
left of the screen. Do you have any ideas why this happens??
I hope you can help me,
Thanks
Guido Krueger
Juergen Wieferink
>> >> set datafile separator "\t" # tab-separated data
>> >> set view map # 2D plot with Z value encoding
color
>> >> set palette gray # grayscale color mapping
>> >> set zrange [0:1] # force full range of color scale
>> >>
>> >> plot "data" using 1:2:3 with points pt 6 ps .5 palette
>> >
>> >Having updated gnuplot, this last line of your suggestion is giving the
>> >error "Too many using specs for this style".
>>
>> Sorry. That should have been "splot" rather than "plot".
>
> Hello, I have the same problem. With splot I can plot the points with
> different intensities, but if I change the pointsize, the points move
> to another position!
> With increasing pointsize the hole grid of points is moving to the
> left of the screen. Do you have any ideas why this happens??
>
> I hope you can help me,
I can't reproduce that. Could you give a minimal example? Something
like:
set view map
set palette gray
splot "-" with points palette
1.1, 1.1, 1
1.1, 1.9, 1.5
1.9, 1.1, 1.25
1.9, 1.9, 1.75
e
splot "-" with points ps 5 palette
1.1, 1.1, 1
1.1, 1.9, 1.5
1.9, 1.1, 1.25
1.9, 1.9, 1.75
e
Juergen
PS: "show version"
Guido Krueger
>
> I can't reproduce that. Could you give a minimal example? Something
> like:
>
> set view map
> set palette gray
> splot "-" with points palette
> 1.1, 1.1, 1
> 1.1, 1.9, 1.5
>
> 1.9, 1.1, 1.25
> 1.9, 1.9, 1.75
> e
>
> splot "-" with points ps 5 palette
> 1.1, 1.1, 1
> 1.1, 1.9, 1.5
>
> 1.9, 1.1, 1.25
> 1.9, 1.9, 1.75
> e
>
>
> Juergen
>
> PS: "show version"
I use the version 4.0 patchlevel 0.
And now I know why this happens, the points in my graph are to big to
fit in the borders ( I have 128x128 points, 2 graphs per sheet, so ps
1 is already too much). The points intersect each other and they
seemed to move left ( just increase the ps further), because the
remaining part of the color is in the lower left corner. Also my color
palette is build so, that small numbers get a white point and high
numbers get colored points (so I can see the Fourier-components of the
calculations I made very clearly).
So the I solve the problem just by keeping the ps under an appriciate
level.
But thank you for thinking about it,
Guido Krueger