gnuplot-info — For questions and discussion about gnuplot

Re: [Gnuplot-info] empty x range

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

set xrange ["12/28/2010":"12/28/2010"]

start and end time are the same, so the x-range is empty.


fretagi wrote:
> 
> I am trying to generate a plot from a txt file that looks like this:
> 
> 12/28/2010 00:00:00      4  25.62      670.1      200426      9674  68.27 
> 52.59  49.00           0        0.0
> 12/28/2010 00:05:00      4  19.58      304.8       91592      9697  68.19 
> 52.52  49.00           0        0.0
> 12/28/2010 00:10:00      4  14.54      187.4       56276      9736  68.08 
> 52.41  49.00           0        0.0
> 12/28/2010 00:15:00      4  15.77      192.7       57867      9722  68.11 
> 52.44  49.00           0        0.0
> 12/28/2010 00:20:00      4  13.75      173.0       51761      9681  68.25 
> 52.57  49.00           0        0.0
> 12/28/2010 00:25:00      4  13.61      186.4       56069      9639  68.36 
> 52.69  49.00           0        0.0
> 12/28/2010 00:30:00      4  18.18      383.4      115211      9598  68.50 
> 52.82  49.00           0        0.0
> 
> and I am using the following file:
> 
> set terminal png truecolor
> set output "glox1.png"
> set autoscale
> set xdata time
> set timefmt "%m/%d/%Y"
> set xrange ["12/28/2010":"12/28/2010"]
> set format x "%m/%d"
> set timefmt "%m/%d/%Y\t%H:%M:%S"
> set style data lines
> plot "glo1.txt" using 1:4 
> 
> 
> But I am getting the following error:
> gnuplot> plot "glo1.txt" using 1:4
>                                   ^
>          line 0: Can't plot with an empty x range!
> 
> Please can you help me solve this issue
> 

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Re: [Gnuplot-info] Need help: Time/date format

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

in gnuplot version >= 4.4 you could use the following plot command:

plot 'datafilename' using
1:(s=stringcolumn(2),n=strstrt(s,":"),s[1:n-1]+s[n+1:]/60.) with linespoints


david-825 wrote:
> 
> currently gnuplot only supports time on the X axis, what you would need to 
> do is to manipulate the data before gnuplot tries to use it.
> 
> you could do soemthing like the following perl snippet
> 
> #!/usr/bin/perl
> while(<>){
>    chomp;
>    ($first,$second) = split(":",$_);
>    print $first,".",($second/60),"\n";
> }
> 
> this will reformat the lines you listed to something like
> 
> 2010-12-07 8.00
> 
> so that instead of integer hours it will read decimal hours.
> 
> If your Y axis ticks are on the hour, the graph will look the same. If you 
> want tick marks in between, you would need to do something like setting 
> the tick label for 7.5 to be "7:30"
> 
> David Lang
> 
> On Wed, 5 Jan 2011, steffen wrote:
> 
>> Date: Wed, 5 Jan 2011 10:07:50 +0000 (UTC)
>> From: steffen <kla...@on...>
>> To: gnu...@li...
>> Subject: [Gnuplot-info] Need help: Time/date format
>> 
>> Hi,
>> I'm going to generate a plot of sunrise time versus date.
>> The data file looks like
>>
>> 2010-12-02 7:53
>> 2010-12-03 7:55
>> 2010-12-06 7:59
>> 2010-12-07 8:00
>> ...
>>
>> So, in the first column is the date (shall be x-axis), in the second the
>> time
>> (y-axis). To read the date correctly I did:
>>
>> set xdata time
>> set timefmt "%Y-%m-%d"
>>
>> But the time (y-axis) is not read correctly, just integer hours. How to
>> set up
>> the format (time) for the y-axis?
>>
>> Thanks for help.
>>
>>
>>
>> ------------------------------------------------------------------------------
>> Learn how Oracle Real Application Clusters (RAC) One Node allows
>> customers
>> to consolidate database storage, standardize their database environment,
>> and,
>> should the need arise, upgrade to a full multi-node Oracle RAC database
>> without downtime or disruption
>> http://p.sf.net/sfu/oracle-sfdevnl
>> _______________________________________________
>> gnuplot-info mailing list
>> gnu...@li...
>> https://lists.sourceforge.net/lists/listinfo/gnuplot-info
>>
> 
> ------------------------------------------------------------------------------
> Learn how Oracle Real Application Clusters (RAC) One Node allows customers
> to consolidate database storage, standardize their database environment,
> and, 
> should the need arise, upgrade to a full multi-node Oracle RAC database 
> without downtime or disruption
> http://p.sf.net/sfu/oracle-sfdevnl
> _______________________________________________
> gnuplot-info mailing list
> gnu...@li...
> https://lists.sourceforge.net/lists/listinfo/gnuplot-info
> 
> 

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[Gnuplot-info] empty x range

[fretagi <fr...@mc...>]

I am trying to generate a plot from a txt file that looks like this:

12/28/2010 00:00:00      4  25.62      670.1      200426      9674  68.27 
52.59  49.00           0        0.0
12/28/2010 00:05:00      4  19.58      304.8       91592      9697  68.19 
52.52  49.00           0        0.0
12/28/2010 00:10:00      4  14.54      187.4       56276      9736  68.08 
52.41  49.00           0        0.0
12/28/2010 00:15:00      4  15.77      192.7       57867      9722  68.11 
52.44  49.00           0        0.0
12/28/2010 00:20:00      4  13.75      173.0       51761      9681  68.25 
52.57  49.00           0        0.0
12/28/2010 00:25:00      4  13.61      186.4       56069      9639  68.36 
52.69  49.00           0        0.0
12/28/2010 00:30:00      4  18.18      383.4      115211      9598  68.50 
52.82  49.00           0        0.0

and I am using the following file:

set terminal png truecolor
set output "glox1.png"
set autoscale
set xdata time
set timefmt "%m/%d/%Y"
set xrange ["12/28/2010":"12/28/2010"]
set format x "%m/%d"
set timefmt "%m/%d/%Y\t%H:%M:%S"
set style data lines
plot "glo1.txt" using 1:4 


But I am getting the following error:
gnuplot> plot "glo1.txt" using 1:4
                                  ^
         line 0: Can't plot with an empty x range!

Please can you help me solve this issue
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Re: [Gnuplot-info] Need help: Time/date format

[steffen <kla...@on...>]

Thanks for the exhaustive answer. The perl script will help.
Steffen

Re: [Gnuplot-info] Need help: Time/date format

[<da...@la...>]

currently gnuplot only supports time on the X axis, what you would need to 
do is to manipulate the data before gnuplot tries to use it.

you could do soemthing like the following perl snippet

#!/usr/bin/perl
while(<>){
   chomp;
   ($first,$second) = split(":",$_);
   print $first,".",($second/60),"\n";
}

this will reformat the lines you listed to something like

2010-12-07 8.00

so that instead of integer hours it will read decimal hours.

If your Y axis ticks are on the hour, the graph will look the same. If you 
want tick marks in between, you would need to do something like setting 
the tick label for 7.5 to be "7:30"

David Lang

On Wed, 5 Jan 2011, steffen wrote:

> Date: Wed, 5 Jan 2011 10:07:50 +0000 (UTC)
> From: steffen <kla...@on...>
> To: gnu...@li...
> Subject: [Gnuplot-info] Need help: Time/date format
> 
> Hi,
> I'm going to generate a plot of sunrise time versus date.
> The data file looks like
>
> 2010-12-02 7:53
> 2010-12-03 7:55
> 2010-12-06 7:59
> 2010-12-07 8:00
> ...
>
> So, in the first column is the date (shall be x-axis), in the second the time
> (y-axis). To read the date correctly I did:
>
> set xdata time
> set timefmt "%Y-%m-%d"
>
> But the time (y-axis) is not read correctly, just integer hours. How to set up
> the format (time) for the y-axis?
>
> Thanks for help.
>
>
>
> ------------------------------------------------------------------------------
> Learn how Oracle Real Application Clusters (RAC) One Node allows customers
> to consolidate database storage, standardize their database environment, and,
> should the need arise, upgrade to a full multi-node Oracle RAC database
> without downtime or disruption
> http://p.sf.net/sfu/oracle-sfdevnl
> _______________________________________________
> gnuplot-info mailing list
> gnu...@li...
> https://lists.sourceforge.net/lists/listinfo/gnuplot-info
>

[Gnuplot-info] Need help: Time/date format

[steffen <kla...@on...>]

Hi,
I'm going to generate a plot of sunrise time versus date. 
The data file looks like

2010-12-02 7:53
2010-12-03 7:55
2010-12-06 7:59
2010-12-07 8:00
...

So, in the first column is the date (shall be x-axis), in the second the time
(y-axis). To read the date correctly I did:

set xdata time
set timefmt "%Y-%m-%d"

But the time (y-axis) is not read correctly, just integer hours. How to set up
the format (time) for the y-axis?

Thanks for help.

[Gnuplot-info] Plot 3D Array as 2D Image

[<Ste...@gm...>]

Hi,

I want to plot a three dimensional array from a binary file as 2D images. Each array element contains a float32 value. 

The plot command 
#####################################
plot 'test3D.dat' binary array=16x16x16 format='%float32'  using ($1) with image
#####################################
works in principle. But how is it possible to define which layer (for example third layer of the second dimension) should be plotted. 

Or is it not possible at all so far. 

         Best regards
                     Stefan

Re: [Gnuplot-info] Using palette with 2D Plot

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

use the special filename '+' (you need gnuplot version >= 4.4):

s = 100
xmin = -0.5*pi
xmax = 1.5*pi

set samples s
set xrange [xmin:xmax]

# needed for version 4.4.0
set cbrange [0:2]

plot '+' using 1:(sin($1)+1):((xmax-xmin)/(s-1)):(sin($1)+1) with boxes
palette


sprobst wrote:
> 
> Hi,
> 
> I want to try to get either a line plot or a histogram plot where the
> height is defines also the color. Very useful would be to have the palette
> function. 
> 
> Is it possible to do something like 
> 
> ######################################
> plot sin(x)+1 with boxes palette
> ######################################
> 
> I tried that and sometimes obtained a weird coloring and sometimes only
> black boxes. 
> 
> Thank you for your help.
> 
> ------------------------------------------------------------------------------
> Learn how Oracle Real Application Clusters (RAC) One Node allows customers
> to consolidate database storage, standardize their database environment,
> and, 
> should the need arise, upgrade to a full multi-node Oracle RAC database 
> without downtime or disruption
> http://p.sf.net/sfu/oracle-sfdevnl
> _______________________________________________
> gnuplot-info mailing list
> gnu...@li...
> https://lists.sourceforge.net/lists/listinfo/gnuplot-info
> 
> 

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[Gnuplot-info] Using palette with 2D Plot

[<Ste...@gm...>]

Hi,

I want to try to get either a line plot or a histogram plot where the height is defines also the color. Very useful would be to have the palette function. 

Is it possible to do something like 

######################################
plot sin(x)+1 with boxes palette
######################################

I tried that and sometimes obtained a weird coloring and sometimes only black boxes. 

Thank you for your help.

Re: [Gnuplot-info] one problem

[e-letter <in...@gm...>]

> ------------------------------
>
> Message: 9
> Date: Mon, 3 Jan 2011 01:22:31 +0330
> From: farrokh yousefi <you...@gm...>
> Subject: [Gnuplot-info] one problem
> To: gnu...@li...
> Message-ID:
> 	<AAN...@ma...>
> Content-Type: text/plain; charset=ISO-8859-1
>
> Hi Authors
>
> When I plot a graph by using gnuplot then there will be appear  file name on
> top right of graph.
> I mean if I write command {plot "example.data" using 1:2 with lines} then on
> top right of graph has been written {"example.data" using 1:2}.
> How to vanish or erase it?
>
use the command:

unset key

Re: [Gnuplot-info] one problem

[Hans-Bernhard B. <HBB...@t-...>]

On 02.01.2011 22:52, farrokh yousefi wrote:

> When I plot a graph by using gnuplot then there will be appear  file name on
> top right of graph.

Actually, there's the filename plus a sample of what the data from that 
file are plotted as.  The whole construct is known as the "key", or 
"legend" of the plot.

> I mean if I write command {plot "example.data" using 1:2 with lines} then on
> top right of graph has been written {"example.data" using 1:2}.
> How to vanish or erase it?

Read "help plot title" and "help set key"

[Gnuplot-info] one problem

[farrokh y. <you...@gm...>]

Hi Authors

When I plot a graph by using gnuplot then there will be appear  file name on
top right of graph.
I mean if I write command {plot "example.data" using 1:2 with lines} then on
top right of graph has been written {"example.data" using 1:2}.
How to vanish or erase it?

Thanks in advance
Farrokh

[Gnuplot-info] File name problem

[farrokh y. <you...@gm...>]

Hi Authors

When I plot a graph by using gnuplot then there will be file name on top
right of graph.
I mean if I write command {plot "example.data" using 1:2 with lines} then on
top right of graph has been written {"example.data" using 1:2}.
How to vanish or erase it?

Thanks in advance
Farrokh

Re: [Gnuplot-info] Values to be discarded ...

[Dr. I. D. J. <die...@t-...>]

Thanks,
this was exactly what I have been looking for!
Happy new year,
take care




Dieter Jurzitza

Am Freitag, 31. Dezember 2010, 19:39:19 schrieb Hans-Bernhard Bröker:
> You're searching for 'help missing'
************

-- 
-----------------------------------------------------------

                               |
                                \
                 /\_/\           |
                | ~x~ |/-----\   /
                 \   /-       \_/
  ^^__   _        /  _  ____   /
 <°°__ \- \_/     |  |/    |  |
  ||  ||         _| _|    _| _|

if you really want to see the pictures above - use some font
with constant spacing like courier! :-)
-----------------------------------------------------------

Re: [Gnuplot-info] Values to be discarded ...

[Hans-Bernhard B. <HBB...@t-...>]

On 31.12.2010 16:00, Dr. Ing. Dieter Jurzitza wrote:

> If I try to plot as depicted above, I'll fail as there are no more valid data
> in column 2 above the x-value 5. Is there any "dummy" value available telling
> the plot command to count as a valid element of column (I.e. 2) but not to be
> plotted?

You're searching for 'help missing'

[Gnuplot-info] Values to be discarded ...

[Dr. I. D. J. <die...@t-...>]

Dear listmembers,
I have a file consisting of columns, say, 1 to 5.
I plot the data via
plot "<filename>" using 1:2 w l lw 2,\
     "<filename>" using 1:3 w l lw 2,\
     "<filename>" using 1:4 w l lw 2,\
     "<filename>" using 1:5 w l lw 2
so far, so good. Now, say, there are no more data in column two above a 
threshold value "x", being "x" an element of column 1:

1   2   3
2   4   5
3   5   7
4   6   6
5   3   4
6       3
7
8

If I try to plot as depicted above, I'll fail as there are no more valid data 
in column 2 above the x-value 5. Is there any "dummy" value available telling 
the plot command to count as a valid element of column (I.e. 2) but not to be 
plotted? Currently I filled in values that are so large that they do not show 
and I extrapolated the curve roughly so it would touch that value - but this 
is not what I'd like to see.

I hope my explanation is sufficiently clear.

Many thanks for your efforts, a happy new Year!

Take care


Dieter Jurzitza


-- 
-----------------------------------------------------------

                               |
                                \
                 /\_/\           |
                | ~x~ |/-----\   /
                 \   /-       \_/
  ^^__   _        /  _  ____   /
 <°°__ \- \_/     |  |/    |  |
  ||  ||         _| _|    _| _|

if you really want to see the pictures above - use some font
with constant spacing like courier! :-)
-----------------------------------------------------------

Re: [Gnuplot-info] contour labels in key

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

until somebody builds this *axis label<->string assignment mechanism
into 'clabel', you could change the clabel format to add a unit:

set clabel "%.0f seconds"


tom fogal-2 wrote:
> 
> I've been playing with
> 
>   set contour surface
> 
> and seen some nice results.  However one issue I'm having is that I can
> select the contour values explicitly, as I'd like:
> 
>   set cntrparam levels discrete 60, 300, 600, 1800
> 
> but then they appear in my legend as "60", "300", etc.  In my current
> case, those happen to represent seconds, so I'd like the labels to say
> "A minute", "5 minutes", etc.  I have not yet found a way to do this.
> 
> It would be really great if the discrete list could accept the same
> syntax as the "set ?tics" commands, e.g.:
> 
>   set cntrparam levels discrete ("A minute" 60, "5 minutes" 300, \
>                                  "10 minutes" 600, "Half hour" 1800)
> 
> Perhaps there's another way to achieve what I'm looking for, though?
> 
> Currently using 4.2, which is most convenient, but I've got 4.4 at home
> and could upgrade here if I really needed to.
> 
> Thanks,
> 
> -tom
> 
> ------------------------------------------------------------------------------
> Learn how Oracle Real Application Clusters (RAC) One Node allows customers
> to consolidate database storage, standardize their database environment,
> and, 
> should the need arise, upgrade to a full multi-node Oracle RAC database 
> without downtime or disruption
> http://p.sf.net/sfu/oracle-sfdevnl
> _______________________________________________
> gnuplot-info mailing list
> gnu...@li...
> https://lists.sourceforge.net/lists/listinfo/gnuplot-info
> 
> 

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Re: [Gnuplot-info] multi-column key displays

[<da...@la...>]

On Fri, 31 Dec 2010, Hans-Bernhard Br?ker wrote:

> On 31.12.2010 00:42, da...@la... wrote:
>> I have a graph that has many items in the key. Is there some way to have
>> the key split into multiple columns so that it can take more horizontal
>> space rather than vertical space?
>> 
>> I'm currently putting the key on the right margin, but some of the values
>> are fairly long, which squashes the graph to the left of the page. I would
>> love to put this in the bottom margin, but unless the key can be put into
>> 3-4 columns, I have a similar problem that it will squash the graph to the
>> top of the page.
>
> 'set key below' already does that.  You could, of course, just use shorter 
> keys instead ;-)

thanks, that is what I was looking for. I didn't find it in the 'gnuplot 
in action' or in the manual. it may be worth calling out explicitly for 
the next update.

David Lang

Re: [Gnuplot-info] multi-column key displays

[Hans-Bernhard B. <HBB...@t-...>]

On 31.12.2010 00:42, da...@la... wrote:
> I have a graph that has many items in the key. Is there some way to have
> the key split into multiple columns so that it can take more horizontal
> space rather than vertical space?
>
> I'm currently putting the key on the right margin, but some of the values
> are fairly long, which squashes the graph to the left of the page. I would
> love to put this in the bottom margin, but unless the key can be put into
> 3-4 columns, I have a similar problem that it will squash the graph to the
> top of the page.

'set key below' already does that.  You could, of course, just use 
shorter keys instead ;-)

[Gnuplot-info] multi-column key displays

[<da...@la...>]

I have a graph that has many items in the key. Is there some way to have 
the key split into multiple columns so that it can take more horizontal 
space rather than vertical space?

I'm currently putting the key on the right margin, but some of the values 
are fairly long, which squashes the graph to the left of the page. I would 
love to put this in the bottom margin, but unless the key can be put into 
3-4 columns, I have a similar problem that it will squash the graph to the 
top of the page.

David Lang

[Gnuplot-info] stacked histograms with date X axis

[<da...@la...>]

Is there a way to create stacked histograms but have the X axis be a date 
value?

I've currently got the histograms correct, each with a label, but I really 
want to have them positioned based on the date rather than having them 
evenly spaced, no matter what the dates are.

David Lang

[Gnuplot-info] contour labels in key

[tom f. <tf...@sc...>]

I've been playing with

  set contour surface

and seen some nice results.  However one issue I'm having is that I can
select the contour values explicitly, as I'd like:

  set cntrparam levels discrete 60, 300, 600, 1800

but then they appear in my legend as "60", "300", etc.  In my current
case, those happen to represent seconds, so I'd like the labels to say
"A minute", "5 minutes", etc.  I have not yet found a way to do this.

It would be really great if the discrete list could accept the same
syntax as the "set ?tics" commands, e.g.:

  set cntrparam levels discrete ("A minute" 60, "5 minutes" 300, \
                                 "10 minutes" 600, "Half hour" 1800)

Perhaps there's another way to achieve what I'm looking for, though?

Currently using 4.2, which is most convenient, but I've got 4.4 at home
and could upgrade here if I really needed to.

Thanks,

-tom

Re: [Gnuplot-info] logscale cb for 2d plots

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

use the pseudo-filename '+' to be able to use the 'using' option
and give the color value as the third component:

...
set style line 1 lt -1 lw 2 lc palette z
...
plot '+' using 1:(a($1)):(log(a($1))) with lines title 'cb=0.05' ls 1, ...



Kevin McPeak wrote:
> 
> Does anyone know if it is possible to use 'set logscale cb' to color a
> set of 2d plots?
> 
> I have attached a script that attempts to do this. The problem I am
> running into is that the colors on the logscaled color bar do not
> match up with the line colors. They do if I revert to a linear cb
> scale but I would really like to keep the cb scale logarithmic. For
> example, the cb=0.1 line (the middle one) should be purple but it is
> orange.
> 
> I have tried running this on v4.4, v4.42 and v4.5(dev) and I get the
> same results.
> 
> The code is below and I attached a file as well. Any help is most
> appreciated.
> 
> Regards,
> Kevin McPeak
> 
> # Gnuplot script file for attempting to use 'set logscale cb' for 2d plots
> 
> reset
> set term windows color
> 
> set size 0.9,1.0
> set origin 0,0
> 
> set logscale cb 10
> set palette model RGB rgbformulae 7,5,15
> set cbrange [0.01:10]
> 
> # Line Styles
> set style line 1 lt -1 lw 2 lc palette cb 0.05
> set style line 2 lt -1 lw 2 lc palette cb 0.1
> set style line 3 lt -1 lw 2 lc palette cb 8
> 
> set lmargin 7
> set rmargin 0.5
> set tmargin 1
> set bmargin 3
> 
> set colorbox vertical user origin 0.9, 0.16 size 0.02,0.80
> set cblabel "cb" rotate by 90 offset -4, 0
> 
> unset label                            # remove any previous labels
> set mxtics 5
> set xtics 0.25
> set ytics 0.25
> set mytics 5
> set pointsize 2
> set xr [0:1]
> set yr [0:1]
> 
> a(x) = 0.5*x
> b(x) = (0.5*x)+0.1
> c(x) = (0.5*x)+0.2
> 
> plot a(x) title 'cb=0.05' ls 1, b(x) title 'cb=0.1' ls 2, c(x) title
> 'cb=8' ls 3
> 
> reset
> 
> # End
> 
> -- 
> Kevin McPeak Ph.D.
> Postdoctoral Researcher
> ETH Zürich
> Optical Materials Engineering Laboratory
> Universitaetsstrasse 6, CNB F121
> CH-8092 Zurich, Switzerland
> Voice: +41 44 632 6594
> Email: km...@et...
> 
> ------------------------------------------------------------------------------
> Learn how Oracle Real Application Clusters (RAC) One Node allows customers
> to consolidate database storage, standardize their database environment,
> and, 
> should the need arise, upgrade to a full multi-node Oracle RAC database 
> without downtime or disruption
> http://p.sf.net/sfu/oracle-sfdevnl
> _______________________________________________
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[Gnuplot-info] Creating arbitrary polygon color map with coordinates and color info

[Minjae K. <mi...@po...>]

Hello,

I have been looking into this problem; there seem to be related questions
online, but not the exact one I wanted.

Basically, I have a file with coordinates of nodes for 2D polygons and
another column for color information to color-fill the polygons. Ideally, I
would want to something like

plot 'polygons.dat' using 1:2:3 with filledcurves lc rgb variable

The problem is that (in my novice eyes) filledcurves command seem to consume
all three columns (creating wierd shapes) and rgb gets no data from the
third column, showing a black figure.

The way I am working around is to plot 3D using pm3d, which supports 3D
faces with colors and I just force plot everthing on a flat surface (i.e. z
= 0).  However, I would really appreciate a more correct solution.

Thanks.

Minjae

[Gnuplot-info] logscale cb for 2d plots

[Kevin M. <km...@et...>]

Does anyone know if it is possible to use 'set logscale cb' to color a
set of 2d plots?

I have attached a script that attempts to do this. The problem I am
running into is that the colors on the logscaled color bar do not
match up with the line colors. They do if I revert to a linear cb
scale but I would really like to keep the cb scale logarithmic. For
example, the cb=0.1 line (the middle one) should be purple but it is
orange.

I have tried running this on v4.4, v4.42 and v4.5(dev) and I get the
same results.

The code is below and I attached a file as well. Any help is most appreciated.

Regards,
Kevin McPeak

# Gnuplot script file for attempting to use 'set logscale cb' for 2d plots

reset
set term windows color

set size 0.9,1.0
set origin 0,0

set logscale cb 10
set palette model RGB rgbformulae 7,5,15
set cbrange [0.01:10]

# Line Styles
set style line 1 lt -1 lw 2 lc palette cb 0.05
set style line 2 lt -1 lw 2 lc palette cb 0.1
set style line 3 lt -1 lw 2 lc palette cb 8

set lmargin 7
set rmargin 0.5
set tmargin 1
set bmargin 3

set colorbox vertical user origin 0.9, 0.16 size 0.02,0.80
set cblabel "cb" rotate by 90 offset -4, 0

unset label                            # remove any previous labels
set mxtics 5
set xtics 0.25
set ytics 0.25
set mytics 5
set pointsize 2
set xr [0:1]
set yr [0:1]

a(x) = 0.5*x
b(x) = (0.5*x)+0.1
c(x) = (0.5*x)+0.2

plot a(x) title 'cb=0.05' ls 1, b(x) title 'cb=0.1' ls 2, c(x) title 'cb=8' ls 3

reset

# End

-- 
Kevin McPeak Ph.D.
Postdoctoral Researcher
ETH Zürich
Optical Materials Engineering Laboratory
Universitaetsstrasse 6, CNB F121
CH-8092 Zurich, Switzerland
Voice: +41 44 632 6594
Email: km...@et...