Re: [Gnuplot-info] unexpected difference between plot and splot of binary files with unstructured data

[cédric ody <cedric.listes@gm...>]

In fact and to be more complete, this behaviour for splot is obtained
with gnuplot 4.6 patchlevel 0.

Crossing lines are also observed for splot AND plot command on the
older version 4.2 patchlevel 2. So it is seems there have been
progress between the two versions for the plot command.

Cédric



2013/9/30, cédric ody <cedric.listes@...>:
> Hi,
>
> I have found a interesting comment on the web explaining how to plot
> unstructured mesh written in a binary file in gnuplot. I knew to do
> that in ascii but I have been looking for the binary possibility for a
> while.
>
> The command is for instance the following
>
> plot 'file.dat' binary record=(15,-1) format='%float' u 1:2:3 w l palette
>
> I wrote the binary file file.dat using octave (fwrite(file,vector)).
>
> The 15 is because I plot cells of 5 points of two coordinates + the
> value at the point.
>
> cell=[ptA ptB ptC ptD ptA]
>
> vector=[ptAx ptAy ptAval ptBx ptBy ptBval ptCx ptCy ptCval  ptDx ptDy
> ptDval  ptAx ptAy ptAval ...];
>
> The plot command gives expected results (I would expect that I have
> used an ascii filename). However, the splot command does not as some
> cells of the unstructured mesh are now connected although they should
> not.
>
> Does anybody know what I am missing.
>
> Thank you very much,
>
> Cédric
>

[Gnuplot-info] unexpected difference between plot and splot of binary files with unstructured data

[cédric ody <cedric.listes@gm...>]

Hi,

I have found a interesting comment on the web explaining how to plot
unstructured mesh written in a binary file in gnuplot. I knew to do
that in ascii but I have been looking for the binary possibility for a
while.

The command is for instance the following

plot 'file.dat' binary record=(15,-1) format='%float' u 1:2:3 w l palette

I wrote the binary file file.dat using octave (fwrite(file,vector)).

The 15 is because I plot cells of 5 points of two coordinates + the
value at the point.

cell=[ptA ptB ptC ptD ptA]

vector=[ptAx ptAy ptAval ptBx ptBy ptBval ptCx ptCy ptCval  ptDx ptDy
ptDval  ptAx ptAy ptAval ...];

The plot command gives expected results (I would expect that I have
used an ascii filename). However, the splot command does not as some
cells of the unstructured mesh are now connected although they should
not.

Does anybody know what I am missing.

Thank you very much,

Cédric

Re: [Gnuplot-info] formatting ytics

[Theo <theozh@gm...>]

 > I sort of hate it when I hear can't be done...
 >
 > set format y "%.sG"
 >
 > John
 >

Really??? At my GnuPlot 4.6 this just adds G at each tic lable.

I think what Mahmood was looking for, e.g.:

set yrange [1e-18:1e18]
set ytics 10
set format y "%.2s %c"

As Bernhard wrote... also look e.g. at the example in the Gnuplot 4.6 
PDF manual, page 113, example 6.

Theo.

Re: [Gnuplot-info] formatting ytics

[Leo Butler <l_butler@us...>]

>   From: Mahmood Naderan <nt_mahmood@...>
>
>   Thanks a lot. I was writing a python script to preprocess the values!
>
>   Just want to know how someone should conclude "%.sG" for such formatting?
>   From the manual http://gnuplot.sourceforge.net/docs_4.2/node184.html, we read:

Mahmood, I would suggest an alternative approach to your problem:
rescale your y values and include the scale information in the ylabel
rather than in the tick labels.

Leo

Re: [Gnuplot-info] formatting ytics

[Mahmood Naderan <nt_mahmood@ya...>]

Thanks a lot. I was writing a python script to preprocess the values!

Just want to know how someone should conclude "%.sG" for such formatting?
From the manual http://gnuplot.sourceforge.net/docs_4.2/node184.html, we read:



If the format string is omitted, the format will
be returned to the default "% g"
...
%e or %E exponential notation; an "e" or "E" before the power
%g or %G the shorter of %e (or %E) and %f
...
The default format for both axes is "% g", but other formats such as "%.2f" or "%3.0em" are often desirable
....
Characters not preceded by "%" are printed verbatim.  Thus you can include
spaces and labels in your format string, such as "%g m", which will put " m" after each number.  If you want "%" itself, double it: "%g %%". 



 
Regards,
Mahmood



________________________________
 From: BBands <bbands@...>
To: gnuplot <gnuplot-info@...> 
Sent: Friday, September 27, 2013 9:11 PM
Subject: Re: [Gnuplot-info] formatting ytics
 

I sort of hate it when I hear can't be done...

set format y "%.sG"

John

On Fri, Sep 27, 2013 at 10:25 AM, Mahmood Naderan <nt_mahmood@...> wrote:
> Yes I know that but these specifiers are good for hex and scientific numbers
> (for example 0x7F, 0x7f, 2E+2, e2+2). None of them convert a 3,000,000,000
> number to 3G.
> I think I have to write a script to preprocess that. Thanks

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Re: [Gnuplot-info] formatting ytics

[BBands <bbands@gm...>]

I sort of hate it when I hear can't be done...

set format y "%.sG"

John

On Fri, Sep 27, 2013 at 10:25 AM, Mahmood Naderan <nt_mahmood@...> wrote:
> Yes I know that but these specifiers are good for hex and scientific numbers
> (for example 0x7F, 0x7f, 2E+2, e2+2). None of them convert a 3,000,000,000
> number to 3G.
> I think I have to write a script to preprocess that. Thanks

Re: [Gnuplot-info] formatting ytics

[Hans-Bernhard Bröker <HBBroeker@T-Online.de>]

Am 27.09.2013 19:25, schrieb Mahmood Naderan:
> Yes I know that but these specifiers are good for hex and scientific numbers (for example 0x7F, 0x7f, 2E+2, e2+2). None of them convert a 3,000,000,000 number to 3G.
> I think I have to write a script to preprocess that. Thanks

No, you don't.  You only need to read all of "help set format", 
including the examples, and use what you learnt there.

Re: [Gnuplot-info] formatting ytics

[Mahmood Naderan <nt_mahmood@ya...>]

Yes I know that but these specifiers are good for hex and scientific numbers (for example 0x7F, 0x7f, 2E+2, e2+2). None of them convert a 3,000,000,000 number to 3G.
I think I have to write a script to preprocess that. Thanks

 
Regards,
Mahmood



________________________________
 From: BBands <bbands@...>
To: gnuplot <gnuplot-info@...> 
Sent: Friday, September 27, 2013 8:30 PM
Subject: Re: [Gnuplot-info] formatting ytics
 

There are better examples here:

http://www.cplusplus.com/reference/cstdio/printf/

Best,

John

On Fri, Sep 27, 2013 at 9:48 AM, Mahmood Naderan <nt_mahmood@...> wrote:
>
>>set format y "%c"
> It just show
> G
> G
> G
> M
> there is no number

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Re: [Gnuplot-info] formatting ytics

[BBands <bbands@gm...>]

There are better examples here:

http://www.cplusplus.com/reference/cstdio/printf/

Best,

John

On Fri, Sep 27, 2013 at 9:48 AM, Mahmood Naderan <nt_mahmood@...> wrote:
>
>>set format y "%c"
> It just show
> G
> G
> G
> M
> there is no number

Re: [Gnuplot-info] formatting ytics

[BBands <bbands@gm...>]

Mahmood,

gnuplot formatting is very similar to C, so you can do just about
anything you like. There is a good outline of the possibilities here.

http://www.cplusplus.com/reference/cstdio/fprintf/

HTH,

    John

On Fri, Sep 27, 2013 at 9:48 AM, Mahmood Naderan <nt_mahmood@...> wrote:
>
>>set format y "%c"
> It just show
> G
> G
> G
> M
> there is no number

Re: [Gnuplot-info] formatting ytics

[Mahmood Naderan <nt_mahmood@ya...>]

>set format y "%c"
It just show
G
G
G
M
there is no number
 
Regards,
Mahmood



________________________________
 From: Theo <theozh@...>
To: gnuplot-info@... 
Sent: Friday, September 27, 2013 7:32 PM
Subject: Re: [Gnuplot-info] formatting ytics
 

set format y "%c"


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Re: [Gnuplot-info] formatting ytics

[Theo <theozh@gm...>]

set format y "%c"

[Gnuplot-info] formatting ytics

[Mahmood Naderan <nt_mahmood@ya...>]

Hi
Is there anyway to rename the y values from scientific to characters? for example "3e+9" to "3G".
There are some formatting methods with '%' but I can not find which one can do the job.

 
Regards,
Mahmood

Re: [Gnuplot-info] input date format: week numbers + year

[Sebastien Kramm <seb_kramm@ya...>]

Hello,

On 09/25/2013 10:26 PM, Hans-Bernhard Bröker wrote:
> Well, if you decided not to tell gnuplot in any way, shape or form, that this are
>  dates, rather than ordinary numbers, how is it supposed to know that?

Thank you for answering. I am well aware that I need to tell gnuplot in some way that 
this is date-related data, my question was how ;-)

> See "help time/date", and particularly "help timefmt".

Indeed, the last command is what I was looking for (input date format)

> You'll have to change your input format, too.  Week-of-year is not a supported
> date format.

Ok, I will change the data in file, add a field with a valid date format that can be 
read and plotted with a correct ranking by gnuplot, and use xticslabel to have week 
numbers on the x-axis. I'll let you know..

Re: [Gnuplot-info] No bar border in clustered histogram?

[Ethan A Merritt <eamerritt@gm...>]

On Thursday, 26 September 2013, Brian Osborne wrote:
> All,
> 
> I'm making nice clustered histograms but sometimes there are so many bars in the cluster and the bars are so narrow that there's no space within the bars to color, they are all black. Not so informative!
> 
> Here's example code:
> 
> reset
> set title 'Test'
> set terminal svg
> set output test.svg
> set style fill solid 1.00 border lt -1
> set style data histograms
> set style histogram clustered gap 1
> set xtics border rotate by -90
> set auto x
> 
> How do I tell gnuplot either to have no bar border or set the border to the same color as the bar?

  set style fill solid 1.0 noborder
 
> Thanks again,
> 
> Brian O.
-- 
Tradition is not the worship of ashes, but the preservation of fire.
  - Gustav Mahler

[Gnuplot-info] No bar border in clustered histogram?

[Brian Osborne <bosborne11@ve...>]

All,

I'm making nice clustered histograms but sometimes there are so many bars in the cluster and the bars are so narrow that there's no space within the bars to color, they are all black. Not so informative!

Here's example code:

reset
set title 'Test'
set terminal svg
set output test.svg
set style fill solid 1.00 border lt -1
set style data histograms
set style histogram clustered gap 1
set xtics border rotate by -90
set auto x

How do I tell gnuplot either to have no bar border or set the border to the same color as the bar?

Alternatively I guess I could make the diagram much wider, would that work?

Thanks again,

Brian O.

Re: [Gnuplot-info] input date format: week numbers + year

[Hans-Bernhard Bröker <HBBroeker@T-Online.de>]

Am 25.09.2013 19:00, schrieb Sebastien Kramm:
> # week;year;value
> 50;2013;10
> 51;2013;11
> 2;2014;12
>
> with:
> plot "datafile" using $1:$3
> then week 2 will appear *before* week 51, and what I want on the x-axis is:

Well, if you decided not to tell gnuplot in any way, shape or form, that 
this are dates, rather than ordinary numbers, how is it supposed to know 
that?  See "help time/date", and particularly "help timefmt".

You'll have to change your input format, too.  Week-of-year is not a 
supported date format.

[Gnuplot-info] input date format: week numbers + year

[Sebastien Kramm <seb_kramm@ya...>]

Dear gnuplot users and developpers,

I want to plot a datafile were the x-axis data values are the week numbers of a year, 
stored in the datafile. I am producing the datafile from some other application, so I 
can easily change what is stored in it, if needed.

My problem is that for a given year (from september to july), week 2 is after week 
51. If I plot the following toy file:

# week;year;value
50;2013;10
51;2013;11
2;2014;12

with:
plot "datafile" using $1:$3
then week 2 will appear *before* week 51, and what I want on the x-axis is:

50   51   2

I checked out the "set format" command, but it seems to be only about format 
rendering, my problem is about input date format.

Any hint on the easiest way to do this ?

Thank you

Re: [Gnuplot-info] string variables and iteration (gnuplot 4.6)

[Leo Butler <l_butler@us...>]

>   From: Leo Butler <l_butler@...>
>   CC: <gnuplot-info@...>
>
>
>   >   Date: Thu, 19 Sep 2013 04:51:31 -0700
>   >   From: "atoms.h" <thomas.pflueger@...>
>   >   Content-Type: text/plain; charset="us-ascii"
>   >
>   >   Hi,
>   >
>   >   I'm trying to make use of the iteration feature, so far unsuccessfully. I
>   >   want to plot files in different directories with the same file name. All in
>   >   one pdf documents. The way I construct my paths is by means of string
>   >   variables:
>   >
>   >   $ basefolder = '../data/scalePr/'
>   >   $ folder1 = '0.90'
>   >   $ folder2 = '0.95'
>   >   $ folder3 = '0.97'
>   >   $ folder4 = '1.00'
>   >   $ file1 = basefolder.folder1."/".filename.".dat"
>   >   $ file2 = basefolder.folder2."/".filename.".dat"
>   >   $ file3 = basefolder.folder3."/".filename.".dat"
>   >   $ file4 = basefolder.folder4."/".filename.".dat"
>   >
>   >   I haven't figured out a way to iterate through variable names like
>   >
>   >   $ file(n) = basefolder.folder.sprintf("%d",n)."/".filename.".dat"
>   >
>   >   (which obviously doesn't work) to be able to do multiple plots in one
>   >   command:
>   >
>   >   $ do for [i=1:4]{
>   >   $     splot file(i)
>   >   $ }
>   >
>   >   If anyone has an idea how to iterate variable names it would be most
>   >   appreciated!
>
>   It is probably best to use strings with separators to implement a type
>   of read-only string array. Here is one such effort
>
>   gnuplot> directory="/home/user"
>   gnuplot> files="a0 a1 a2 a3 "
>   gnuplot> sep=" "
>   gnuplot> c=strstrt(files,sep);
>   gnuplot>
>   gnuplot> while (c) { w=sprintf("%s/%s",directory,files[0:c-1]);
>   more> print w;
>   more> files=files[c+1:*]
>   more> c=strstrt(files,sep);
>   more> }
>   /home/user/a0
>   /home/user/a1
>   /home/user/a2
>   /home/user/a3
>
>   With a bit more work you can make a custom iterator:
>
>   gnuplot> files="a0 a1 a2 a3 a4 a5 a6 "
>   gnuplot> iterate_over_(string,sep,cmd,s,c)=(c == 0 ? s :\
>   >iterate_over_(string[c+1:*],sep,cmd,s . (c == -1 ? "" : sprintf(cmd,string[0:with_iterate_over_c-1])), strstrt(string[c+1:*],sep)));

That should have been:

iterate_over_(string,sep,cmd,s,c)=(c == 0 ? s :\
iterate_over_(string[c+1:*],sep,cmd,s . (c == -1 ? "" : sprintf(cmd,string[0:c-1])), strstrt(string[c+1:*],sep)));

I made a mistake copying from my work buffer, I guess.

To explain: iterate_over_ is a tail-recursive function that
recursively assembles a command string s, using the sprintf prototype
cmd, and the input string string which is separated by sep.

>   gnuplot> iterate_over(string,sep,cmd)=iterate_over_(string,sep,cmd,"",-1);

You can eval the output of iterate_over, or you could define a 3rd
function that does that for you.

>   gnuplot>
>   gnuplot> print iterate_over(files,sep,"file='%s'; splot directory .'/'. file;\n")
>   file='a0'; splot directory .'/'. file;
>   file='a1'; splot directory .'/'. file;
>   file='a2'; splot directory .'/'. file;
>   file='a3'; splot directory .'/'. file;
>   file='a4'; splot directory .'/'. file;
>   file='a5'; splot directory .'/'. file;
>   file='a6'; splot directory .'/'. file;

Leo

Re: [Gnuplot-info] string variables and iteration (gnuplot 4.6)

[Leo Butler <l_butler@us...>]

>   Date: Thu, 19 Sep 2013 04:51:31 -0700
>   From: "atoms.h" <thomas.pflueger@...>
>   Content-Type: text/plain; charset="us-ascii"
>
>   Hi,
>
>   I'm trying to make use of the iteration feature, so far unsuccessfully. I
>   want to plot files in different directories with the same file name. All in
>   one pdf documents. The way I construct my paths is by means of string
>   variables:
>
>   $ basefolder = '../data/scalePr/'
>   $ folder1 = '0.90'
>   $ folder2 = '0.95'
>   $ folder3 = '0.97'
>   $ folder4 = '1.00'
>   $ file1 = basefolder.folder1."/".filename.".dat"
>   $ file2 = basefolder.folder2."/".filename.".dat"
>   $ file3 = basefolder.folder3."/".filename.".dat"
>   $ file4 = basefolder.folder4."/".filename.".dat"
>
>   I haven't figured out a way to iterate through variable names like
>
>   $ file(n) = basefolder.folder.sprintf("%d",n)."/".filename.".dat"
>
>   (which obviously doesn't work) to be able to do multiple plots in one
>   command:
>
>   $ do for [i=1:4]{
>   $     splot file(i)
>   $ }
>
>   If anyone has an idea how to iterate variable names it would be most
>   appreciated!

It is probably best to use strings with separators to implement a type
of read-only string array. Here is one such effort

gnuplot> directory="/home/user"
gnuplot> files="a0 a1 a2 a3 "
gnuplot> sep=" "
gnuplot> c=strstrt(files,sep);
gnuplot>
gnuplot> while (c) { w=sprintf("%s/%s",directory,files[0:c-1]);
more> print w;
more> files=files[c+1:*]
more> c=strstrt(files,sep);
more> }
/home/user/a0
/home/user/a1
/home/user/a2
/home/user/a3

With a bit more work you can make a custom iterator:

gnuplot> files="a0 a1 a2 a3 a4 a5 a6 "
gnuplot> iterate_over_(string,sep,cmd,s,c)=(c == 0 ? s :\
>iterate_over_(string[c+1:*],sep,cmd,s . (c == -1 ? "" : sprintf(cmd,string[0:with_iterate_over_c-1])), strstrt(string[c+1:*],sep)));
gnuplot> iterate_over(string,sep,cmd)=iterate_over_(string,sep,cmd,"",-1);
gnuplot>
gnuplot> print iterate_over(files,sep,"file='%s'; splot directory .'/'. file;\n")
file='a0'; splot directory .'/'. file;
file='a1'; splot directory .'/'. file;
file='a2'; splot directory .'/'. file;
file='a3'; splot directory .'/'. file;
file='a4'; splot directory .'/'. file;
file='a5'; splot directory .'/'. file;
file='a6'; splot directory .'/'. file;

Leo

[Gnuplot-info] string variables and iteration (gnuplot 4.6)

[atoms.h <thomas.pflueger@gm...>]

Hi,

I'm trying to make use of the iteration feature, so far unsuccessfully. I
want to plot files in different directories with the same file name. All in
one pdf documents. The way I construct my paths is by means of string
variables:

$ basefolder = '../data/scalePr/'
$ folder1 = '0.90'
$ folder2 = '0.95'
$ folder3 = '0.97'
$ folder4 = '1.00'
$ file1 = basefolder.folder1."/".filename.".dat"
$ file2 = basefolder.folder2."/".filename.".dat"
$ file3 = basefolder.folder3."/".filename.".dat"
$ file4 = basefolder.folder4."/".filename.".dat"

I haven't figured out a way to iterate through variable names like

$ file(n) = basefolder.folder.sprintf("%d",n)."/".filename.".dat"

(which obviously doesn't work) to be able to do multiple plots in one
command:

$ do for [i=1:4]{
$     splot file(i)
$ }

If anyone has an idea how to iterate variable names it would be most
appreciated!

Kind regards,
Thomas



--
View this message in context: http://gnuplot.10905.n7.nabble.com/string-variables-and-iteration-gnuplot-4-6-tp17670.html
Sent from the Gnuplot - User mailing list archive at Nabble.com.

[Gnuplot-info] Rotation about third axis for ‘splot’s?

[Elias Assmann <elias.assmann@gm...>]

Hi,

With ’set view’ (or by dragging with the mouse), I can set two angles of 
rotation for the viewpoint in a ‘splot’: ‘rot_x’ and ‘rot_z’.  Is there 
also a way to set a “rot_y”?

By way of example, consider the following plot of a spiral around the z 
axis (my actual plot is similar, but a bit more complicated.):

set map cyl
set zzeroax ls -1
splot [-5:5] [-5:5] '+' u ($1*pi):1:(1) w l

Now, I would like to have the z axis point “diagonally into the screen”, 
so that it looks like the spiral is going “off into the distance“, if 
you will.  (Note: I am not asking about perspective projection; that 
might be nice for my plot, but is not required.)


	Elias

Re: [Gnuplot-info] Frequency of Points with Linespoints Option

[Ethan A Merritt <eamerritt@gm...>]

On Monday, 09 September 2013, Matthew Clay wrote:
> Hi,
> 
> First, I saw a related post about my question from the late 90's, and
> couldn't find anything else...so I figured I'd email the mailing list.
> The problem is pretty simple: I have line plots with 10000's of data
> points, so differentiating between multiple data sets on a single plot
> is very difficult with setting the linetype (they all pretty much look
> like solid lines). Instead, I'd like to use linespoints with symbols
> popping up at a reasonable frequency. Anybody know how to do this?

Current gnuplot (version 4.6) allows you to attach a "pointinterval"
property, "pi" for short.
See for example the second plot in 
  http://gnuplot.sourceforge.net/demo/dashcolor.html


	Ethan


-- 
Tradition is not the worship of ashes, but the preservation of fire.
  - Gustav Mahler

[Gnuplot-info] Frequency of Points with Linespoints Option

[Matthew Clay <mpclay@gm...>]

Hi,

First, I saw a related post about my question from the late 90's, and
couldn't find anything else...so I figured I'd email the mailing list.
The problem is pretty simple: I have line plots with 10000's of data
points, so differentiating between multiple data sets on a single plot
is very difficult with setting the linetype (they all pretty much look
like solid lines). Instead, I'd like to use linespoints with symbols
popping up at a reasonable frequency. Anybody know how to do this?
Thanks for the help.

Thanks,
Matthew

Re: [Gnuplot-info] fitting a implicit function with gnuplot

[Hans-Bernhard Bröker <HBBroeker@t-...>]

On 05.09.2013 12:52, U Maennl wrote:
> I have the following problem for a school project.
> We collected data from a diode with an resistor in series.
> Now I am trying to fit this data in order to get the value of the series
> resistance.
> The following formula I used:
> I = I0*exp((x-I*Rs)/nkT-1)  (x=V) via I0, Rs, n, T=297
> I know the problem could be solved by change to V = ... but I like to keep
> V on the x-axies.

You'll want to do a "3D fit" of a function that describes your equation, 
i.e., something like this:

	implicit(V,I) = I0*exp((U-I*Rs)/n/k/T - 1.0) - I
	T=297.0
	fit implicit(x,y) 'data' using 1:2:(0.0):(1.0) via I0,Rs,n,T

The drawback is that the z errors are totally bogus, and have no 
relation at all to your data's precision.  So don't put too much trust 
into the result, and none whatsoever into the parameter errors you get.