gnuplot-info — For questions and discussion about gnuplot

Re: [Gnuplot-info] Set key spacing command issues

[Thomas S. <t.s...@fz...>]

please provide a sample script together with information about
which version of gnuplot you are using and which terminal.


Joel Finkeldei wrote:
> 
> I have searched for the answer to this question on numerous occasions with
> no luck. I am hoping someone here has the answer. When I use the "set key
> spacing" command to decrease the space between my key titles the sample
> lines and points do not to readjust along with the titles. I end up with
> the lines sort of "top justified" instead of centered with the label text
> (I can upload a picture if necessary). Does anyone know how to center the
> sample lines with the label text? Any help would be greatly appreciated.
> 

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[Gnuplot-info] Set key spacing command issues

[Joel F. <joe...@gm...>]

I have searched for the answer to this question on numerous occasions with no
luck. I am hoping someone here has the answer. When I use the "set key
spacing" command to decrease the space between my key titles the sample
lines and points do not to readjust along with the titles. I end up with the
lines sort of "top justified" instead of centered with the label text (I can
upload a picture if necessary). Does anyone know how to center the sample
lines with the label text? Any help would be greatly appreciated.
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Re: [Gnuplot-info] Use of multiplot with "set object"

[Thomas S. <t.s...@fz...>]

there is no 'final' plot. 'multiplot' allows a series of
individual plots on the same canvas. and all defined
objects, arrows, labels, ... are drawn for each of
these plots.
the manual says (in the 'multiplot' section):

> Just about everything else that can be set is applied
> to each plot, too. If you want something to appear
> only once on the page, for instance a single time stamp,
> you'll need to put a set time/unset time pair around
> one of the plot, splot or replot commands within the
> set multiplot/unset multiplot block.

the red background box should be drawn only once
and at the beginning of the multiplot series,
otherwise it will cover everything plotted so far.


dbateman wrote:
> 
> 
> 
> Thomas Sefzick wrote:
>> 
>> reset
>> set object 1 rectangle from screen 0,0 to screen 1,1 behind fc rgb
>> "#FF0000"
>> set object 2 rectangle from graph 0,0 to graph 1,1 behind fc rgb
>> "#00FF00"
>> set multiplot layout 2, 1 title "Plot 1"
>> plot sin(x)/x
>> unset object 1
>> set object 2 fc rgb "#0000FF"
>> plot sin(x)/x
>> unset multiplot
>> 
>> 
> 
> That works though it seems a bit strange to me to unset an object before
> plotting the final plot.. 
> 
> Best Wishes
> David
> 
> 

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[Gnuplot-info] C++/gnuplot pipeline issue

[Chris F. <cm...@ca...>]

Maybe somebody can help me out.

I have a C++ program which I want to pipe data to gnuplot such that it can 
display a graph of what is happening as a simulation runs. The pipeline 
itself works fine. What the trouble seems to be is that the program writes 
the data I want displayed to a file which it then commands gnuplot to plot. 
This mostly works, only gnuplot sporadically tells me that it cannot plot 
the datafile because there are no valid points. If I step through the 
program one graph at a time it works fine.

My only suspicion is that gnuplot could be looking for the datafile before 
it has been written to the hard drive and is available again, even though 
C++ is definitely closing and flushing the stream that writes the data. Is 
this likely to be the problem or have I overlooked something? Is there any 
way to solve this?

Thanks,
Beleaguered PhD student

Re: [Gnuplot-info] Use of multiplot with "set object"

[dbateman <dba...@fr...>]

Thomas Sefzick wrote:
> 
> reset
> set object 1 rectangle from screen 0,0 to screen 1,1 behind fc rgb
> "#FF0000"
> set object 2 rectangle from graph 0,0 to graph 1,1 behind fc rgb "#00FF00"
> set multiplot layout 2, 1 title "Plot 1"
> plot sin(x)/x
> unset object 1
> set object 2 fc rgb "#0000FF"
> plot sin(x)/x
> unset multiplot
> 
> 

That works though it seems a bit strange to me to unset an object before
plotting the final plot.. 

Best Wishes
David

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Re: [Gnuplot-info] Use of multiplot with "set object"

[Thomas S. <t.s...@fz...>]

reset
set object 1 rectangle from screen 0,0 to screen 1,1 behind fc rgb "#FF0000"
set object 2 rectangle from graph 0,0 to graph 1,1 behind fc rgb "#00FF00"
set multiplot layout 2, 1 title "Plot 1"
plot sin(x)/x
unset object 1
set object 2 fc rgb "#0000FF"
plot sin(x)/x
unset multiplot


dbateman wrote:
> 
> I'm trying to use multiplot and "set object" together to set a background
> colour and then a colour for each of the plot. I tried something like
> 
> reset
> set object 1 rectangle from screen 0,0 to screen 1,1 behind fc rgb
> "#FF0000"
> set multiplot layout 2, 1 title "Plot 1"
> set object 2 rectangle from graph 0,0 to graph 1,1 behind fc rgb "#00FF00"
> plot sin(x)/x
> set object 3 rectangle from graph 0,0 to graph 1,1 behind fc rgb "#0000FF"
> plot sin(x)/x
> unset mulitplot
> 
> but only the last of the plots appeared. It seems that the background
> colour appears only behind the last plot rather than all of the plots. I
> tried this with the WXT and X11 terminals with the same results. Is there
> a way to put the background colour behind all of the plots?
> 
> Regards
> David
> 
> 

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[Gnuplot-info] Use of multiplot with "set object"

[dbateman <dba...@fr...>]

I'm trying to use multiplot and "set object" together to set a background
colour and then a colour for each of the plot. I tried something like

reset
set object 1 rectangle from screen 0,0 to screen 1,1 behind fc rgb "#FF0000"
set multiplot layout 2, 1 title "Plot 1"
set object 2 rectangle from graph 0,0 to graph 1,1 behind fc rgb "#00FF00"
plot sin(x)/x
set object 3 rectangle from graph 0,0 to graph 1,1 behind fc rgb "#0000FF"
plot sin(x)/x
unset mulitplot

but only the last of the plots appeared. It seems that the background colour
appears only behind the last plot rather than all of the plots. I tried this
with the WXT and X11 terminals with the same results. Is there a way to put
the background colour behind all of the plots?

Regards
David

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Re: [Gnuplot-info] does gnuplot needs libwx_gtk2_richtext-2.8.so to run?

[turtledove <fre...@gm...>]

i compiled gnuplot from source, but another error occurs. when i execute
"make", it response:
"ld: Can't find library for -lX11"

after google it, i reconfigure gnuplot with "./configure --without-gd".

then i success to install gnuplot 4.2.6 with no pic(png, etc) terminal
support. luckly, svg terminal is available.

thanks for your advise!


Thomas Sefzick wrote:
> 
> if the 'dynamic loader' tries to load 'libwx_gtk2_richtext-2.8.so'
> then we can assume that it is needed.
> 
> did you install all the packets which are required to run gnuplot?
> 
>> Run-time dependencies:
>> expat fontconfig freetype gd gettext jpeg libXpm libiconv libpng
>> ncurses readline termcap zlib
> 
> maybe the list is not complete, i'm missing wxGTK.
> should be installed too.
> 
> if you don't need the wxWidgets based 'wxt' terminal then you may
> compile gnuplot by your own.
> 
> 
> turtledove wrote:
>> 
>> I installed gnuplot 4.2.6 on hp-ux(HP-UX 11.31), and i got the binary
>> from
>> http://hpux.connect.org.uk/hppd/hpux/Development/Tools/gnuplot-4.2.6/.
>> 
>> but i when i run gnuplot, i got:
>> /usr/lib/hpux32/dld.so: Unable to find library
>> 'libwx_gtk2_richtext-2.8.so'.
>> Killed
>> 
>> why gnuplot needs libwx_gtk2_richtext to run? how can i resolve this
>> problem?
>> 
>> thanks in advance!
>> 
> 
> 

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Re: [Gnuplot-info] does gnuplot needs libwx_gtk2_richtext-2.8.so to run?

[turtledove <fre...@gm...>]

yes, i have installed all packages in the list.

and, i just want use gnuplot to generate png pic. so, i guess i don't need
wxt terminal to run gnuplot.

is there any way instead of recompile gnuplot by myself? eg. using some
options when run gnuplot?

what confuses me is why gnuplot needs wxt when i don't even use wxt
terminal?


Thomas Sefzick wrote:
> 
> if the 'dynamic loader' tries to load 'libwx_gtk2_richtext-2.8.so'
> then we can assume that it is needed.
> 
> did you install all the packets which are required to run gnuplot?
> 
>> Run-time dependencies:
>> expat fontconfig freetype gd gettext jpeg libXpm libiconv libpng
>> ncurses readline termcap zlib
> 
> maybe the list is not complete, i'm missing wxGTK.
> should be installed too.
> 
> if you don't need the wxWidgets based 'wxt' terminal then you may
> compile gnuplot by your own.
> 
> 
> turtledove wrote:
>> 
>> I installed gnuplot 4.2.6 on hp-ux(HP-UX 11.31), and i got the binary
>> from
>> http://hpux.connect.org.uk/hppd/hpux/Development/Tools/gnuplot-4.2.6/.
>> 
>> but i when i run gnuplot, i got:
>> /usr/lib/hpux32/dld.so: Unable to find library
>> 'libwx_gtk2_richtext-2.8.so'.
>> Killed
>> 
>> why gnuplot needs libwx_gtk2_richtext to run? how can i resolve this
>> problem?
>> 
>> thanks in advance!
>> 
> 
> 

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Re: [Gnuplot-info] data processing

[ZoltánVörös <zv...@gm...>]

Thomas Sefzick <t.sefzick <at> fz-juelich.de> writes:

> 
> 
> you need gnuplot version >= 4.4
> 
> xmin = 999999.
> ymin = 999999.
> # plot something
> set table
> plot 'datafilename' using
> (abs($1)<xmin?xmin=$1:0,$1):(abs($2)<ymin?ymin=$2:0,$2)
> unset table
> print xmin
> print ymin


I think this can be done with some ugly hacking in any version of gnuplot. See
the link below.
Cheers,
Zoltán

http://gnuplot-tricks.blogspot.com/2009/11/some-basic-statistics-with-gnuplot.html

Re: [Gnuplot-info] Better way to do this plotting task?

[Amit S. <lis...@gm...>]

ZoltánVörös wrote:
>> I have a data file with only a single column of say 500 lines. This 500 
>> lines is actually the result of 10 experiments, each of which gives me 
>> 50 lines of data.
>>
>> I would like to tell gnuplot to treat this one file as 10 different sets 
>> of data and not a single big set, i.e it should plot every 50 dataset 
>> and then "replot" over it. (separate colors).
>>
>>
>> Is there a native gnuplot way to do this?
>>
> 
> Yes, you can use the index keyword to specify which data block you want to plot.
> Issue 
> 
> ?index 
> 
> in the gnuplot prompt, and you'll find further information on this.

Great! Thanks Zoltán !

-Amit
> Cheers,
> Zoltán 
> 
> 
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Re: [Gnuplot-info] colour lines

[ZoltánVörös <zv...@gm...>]

> I have a datafile containing x:y value pairs. I'd like to plot it so that
> the colour of the line changes with the y value.
> I'd like to colour it so that for every point of the curve it holds true.
> (What I mean is that a line segment wouldn't be coloured according to the
> end point, but would 'dynamically' change colour according to the current y
> value of the point. Is it possible? 

plot 'foo' u 0:1 smooth cspline with lines lc palette

works, but I don't know how much it distorts your data. 

Cheers,
Zoltán

Re: [Gnuplot-info] Better way to do this plotting task?

[ZoltánVörös <zv...@gm...>]

> I have a data file with only a single column of say 500 lines. This 500 
> lines is actually the result of 10 experiments, each of which gives me 
> 50 lines of data.
> 
> I would like to tell gnuplot to treat this one file as 10 different sets 
> of data and not a single big set, i.e it should plot every 50 dataset 
> and then "replot" over it. (separate colors).
> 
> 
> Is there a native gnuplot way to do this?
> 

Yes, you can use the index keyword to specify which data block you want to plot.
Issue 

?index 

in the gnuplot prompt, and you'll find further information on this.
Cheers,
Zoltán 

Re: [Gnuplot-info] Using gnuplot to plot a graph and include a table with data values in same plot

[ZoltánVörös <zv...@gm...>]

> > I would like to use gnuplot to plot a graph, and to printout a table
> > of data points in the graph in the same plot
> >

I wonder whether something like this would work for you:

plot 'foo' u 1:2 w lp, '' u (8):0:2 axes x1y2 w labels

which will plot 2 versus 1, and put labels with the value of the second column
at (8,0), (8,1), (8,2) etc. (I used the second y axis, so that the labels don't
mess up your line plot.)
Cheers,
Zoltán

Re: [Gnuplot-info] Using gnuplot to plot a graph and include a table with data values in same plot

[Tamas H. <ho...@gm...>]

Wouldn't it be simpler to just generate a html code for the table section?
It should be pretty straightforward.

2010/1/13 Bobo Svangård <bo...@gm...>

> I would like to use gnuplot to plot a graph, and to printout a table
> of data points in the graph in the same plot
>
> I am able to plot a nice looking graph but when i try creating the
> table i seem to be stuck att using a lot of set labels to create a
> non-dynamic table
> Has there been any work done on creating functions to place text and
> tables in the printouts using gnuplot?
>
> /bo svangård
>
>
> ------------------------------------------------------------------------------
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>

[Gnuplot-info] Using gnuplot to plot a graph and include a table with data values in same plot

[Bobo S. <bo...@gm...>]

I would like to use gnuplot to plot a graph, and to printout a table
of data points in the graph in the same plot

I am able to plot a nice looking graph but when i try creating the
table i seem to be stuck att using a lot of set labels to create a
non-dynamic table
Has there been any work done on creating functions to place text and
tables in the printouts using gnuplot?

/bo svangård

[Gnuplot-info] Better way to do this plotting task?

[Amit S. <lis...@gm...>]

Hi all:

Just signed up here. I have been wandering about this question for a 
while now and thought of asking you folks.

I have a data file with only a single column of say 500 lines. This 500 
lines is actually the result of 10 experiments, each of which gives me 
50 lines of data.

I would like to tell gnuplot to treat this one file as 10 different sets 
of data and not a single big set, i.e it should plot every 50 dataset 
and then "replot" over it. (separate colors).

There are two things I have tried so far:

1. Make sure that my program while writing the data, inserts line break 
after a data set (i.e. every 50 lines). The problem with this is that 
all of them are plotted in the same color

2. In the second scenario, I have written a Python script, which reads 
the big data file and creates separate files i.e. 10 files for the 
separate data sets. Then I use gnuplot to plot them, manually (ofcourse 
I could automate this part by making using of pipes).


Is there a native gnuplot way to do this?

Your opinions are welcome.

Thanks,
Amit
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Re: [Gnuplot-info] does gnuplot needs libwx_gtk2_richtext-2.8.so to run?

[Thomas S. <t.s...@fz...>]

if the 'dynamic loader' tries to load 'libwx_gtk2_richtext-2.8.so'
then we can assume that it is needed.

did you install all the packets which are required to run gnuplot?

> Run-time dependencies:
> expat fontconfig freetype gd gettext jpeg libXpm libiconv libpng
> ncurses readline termcap zlib

maybe the list is not complete, i'm missing wxGTK.
should be installed too.

if you don't need the wxWidgets based 'wxt' terminal then you may
compile gnuplot by your own.


turtledove wrote:
> 
> I installed gnuplot 4.2.6 on hp-ux(HP-UX 11.31), and i got the binary from
> http://hpux.connect.org.uk/hppd/hpux/Development/Tools/gnuplot-4.2.6/.
> 
> but i when i run gnuplot, i got:
> /usr/lib/hpux32/dld.so: Unable to find library
> 'libwx_gtk2_richtext-2.8.so'.
> Killed
> 
> why gnuplot needs libwx_gtk2_richtext to run? how can i resolve this
> problem?
> 
> thanks in advance!
> 

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[Gnuplot-info] colour lines

[Tamas H. <ho...@gm...>]

I have a datafile containing x:y value pairs. I'd like to plot it so that
the colour of the line changes with the y value.
I'd like to colour it so that for every point of the curve it holds true.
(What I mean is that a line segment wouldn't be coloured according to the
end point, but would 'dynamically' change colour according to the current y
value of the point. Is it possible? Is it possible with 'smooth'?

Re: [Gnuplot-info] Cant see or plot dashed line curve

[Thomas S. <t.s...@fz...>]

set terminal svg dashed


pban92 wrote:
> 
> 1. I have been trying to plot the following graph
> http://en.wikipedia.org/wiki/File:Hermite_poly.svg in monochrome (black)
> using gnuplot version 4.5 patch level 0 for windows. 
> 2. Could not see the dashed features of the curves, ie, in my case the
> codes from the link produced only solid colored curves.
> 3. Any suggestion would be highly appreciated.
> 4. Thanks!
> 

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[Gnuplot-info] Batch on OSX

[Joe T. <jtr...@ma...>]

Greetings...

I have gnuplot 4.2 patchlevel 6 installed on a Mac OSX 10.5.8 system.
Gnuplot works just fine in interactive mode and with octave.
However, it does not work in batch mode at all.
Never displays a graph.
This must be a OSX thing, since it works just fine on my windows XP  
system.
Is this a bug or is there a workaround?

TIA,
Joe

[Gnuplot-info] Cant see or plot dashed line curve

[pban92 <pb...@ya...>]

1. I have been trying to plot the following graph
http://en.wikipedia.org/wiki/File:Hermite_poly.svg in monochrome (black)
using gnuplot version 4.5 patch level 0 for windows. 
2. Could not see the dashed features of the curves, ie, in my case the codes
from the link produced only solid colored curves.
3. Any suggestion would be highly appreciated.
4. Thanks!
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Re: [Gnuplot-info] animated plot

[Smstry <sm...@gm...>]

here is how i did for whom is interested .(which is almost what Thomas
Sefzick suggested )
suppose Data are in a file called  :    data.dat 
I edited a file which I called plot.gnu
In this file I wrote the following :


     plot "data.dat" u 2:3 every  :::i::i
     if (i<number_of_blocks) reread
     pause 0.2                               



then ,in a terminal you run  gnuplot :

>i=1                                                         # this is to
initialize the value of i (the first block)
>load "plot.gnu"                                          # to run the sript
we wrote 



hope it is clear .

 

Smstry wrote:
> 
> I have a file ( 3 columns x,y,z )which allows me to make a  3D plot .
> i'd like to make an animated 2d plot with this file :i mean for each value
> of x i plot 2d graph ,and i change th evalue of x with time to make
> animation .
> any one could help me ?
> thanks    
>  
> 
> 

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Re: [Gnuplot-info] fit multi-branch (simultaneous fits of 2 data sets)

[Thomas S. <t.s...@fz...>]

yulin chang wrote:
> 
> For simplicity, suppose I had two data sets, both governed by a simple
> exponential decay with the same time constant but different initial
> values,
> i.e., z = a*exp(-t/T) for the first data set and z = b*exp(-t/T) for the
> second,
> and I want to fit the decay for both data sets with a common parameter T.
> 
> In help fit multi-branch of gnuplot, it says
> "The function and parameters (branch) for each data set are selected by
> using a
> 'pseudo-variable', e.g., either the dataline number (a 'column' index of
> -1) or
> the datafile index (-2), as the second independent variable." and in the
> example
> it gives
>       f(x,y) = (y==0) ? a*exp(-x/tau) : b*exp(-x/tau)
>       fit f(x,y) 'datafile' using  1:-2:2:3  via a, b, tau
> 
> Could anybody help me with the following?
> 1. How is f(x,y) switched between a*exp(-x/tau) and b*exp(-x/tau) in the
> fitting
> procedure? Specifically, when the fitting program read a line in the data
> file,
> it sees x:z (first column independent and second column dependent). How
> does the
> program decide which function to use? Since there is no 'y' involved.
> 

sure there is a 'y' involved: it's the 2nd argument of the 'using'
specifier.

in detail:
using  1:-2:2:3
means:
the x-value is read from column 1
the y-value is the current index (=data block) number
the z-value is read from column 2
the s-value is read from column 3

so, if your two data sets are in one file - separated by two empty lines
- then the 1st data set will have the index number '0' and the 2nd index
'1'.
this index is given to the function as y-value which switches between the
two functions.


yulin chang wrote:
> 
> 2. Could anybody give me an example of function and parameters selection
> using
> the dataline number (a 'column' index of -1)?
> 

      f(x,y) = (y<1000) ? a*exp(-x/tau) : b*exp(-x/tau)
      fit f(x,y) 'datafile' using  1:-1:2:3  via a, b, tau

the 1st 1000 data sets (=lines) are fitted using the 1st function,
the remaining data sets are fitted using the 2nd function.


yulin chang wrote:
> 
> Thanks you very much for your help,
> yulin
> 

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[Gnuplot-info] fit multi-branch (simultaneous fits of 2 data sets)

[Yulin C. <cha...@gm...>]

For simplicity, suppose I had two data sets, both governed by a simple
exponential decay with the same time constant but different initial values,
i.e., z = a*exp(-t/T) for the first data set and z = b*exp(-t/T) for the second,
and I want to fit the decay for both data sets with a common parameter T.

In help fit multi-branch of gnuplot, it says
"The function and parameters (branch) for each data set are selected by using a
'pseudo-variable', e.g., either the dataline number (a 'column' index of -1) or
the datafile index (-2), as the second independent variable." and in the example
it gives
      f(x,y) = (y==0) ? a*exp(-x/tau) : b*exp(-x/tau)
      fit f(x,y) 'datafile' using  1:-2:2:3  via a, b, tau

Could anybody help me with the following?
1. How is f(x,y) switched between a*exp(-x/tau) and b*exp(-x/tau) in the fitting
procedure? Specifically, when the fitting program read a line in the data file,
it sees x:z (first column independent and second column dependent). How does the
program decide which function to use? Since there is no 'y' involved.
2. Could anybody give me an example of function and parameters selection using
the dataline number (a 'column' index of -1)?

Thanks you very much for your help,
yulin