All new activity

Need to extract numeric data from a string of ascii

cdbass — Fri, 21 Nov 2008 10:58:04 -0600

I running a monte carlo program that generates ascii data files in multielement lines. Below is a typical example of one of the line:

0.17758E+01 -0.14488E+01 -0.41742E+00 0.85527E+00 -0.47925E-01 -0.51596E+00 0.65037E-05 0.10000E+01 0.69302E+02

I don't have much control over the output format for this data string, except that I have the option of writing the file in binary, but I'm not ready to make that leap yet.

I would like to read in the line and extract each numeric value. I'm fairly new at igor, and I'm having difficulties getting the string functions to do what I want of them. Useful help or advice would be appreciated :)

Igor Pro Wish List

hrodstein — Mon, 09 Jul 2007 21:38:54 -0500

This topic will serve as the IgorPro wish list. Feel free to make suggestions for features that you think would improve Igor Pro.

Note: This discussion is for Igor Pro suggestions only. To make suggestions for IgorExchange.com, please see the IgorExchange.com Wish List discussion.

Programmatically creating waves

Cory K — Fri, 14 Nov 2008 15:34:20 -0600

I am brand new at writing macros (in Igor), so I'm trying to figure stuff out as I go.
One piece of code that I am having trouble with is programmatically creating waves.
In my procedure, heres what I have so far:

Make/N=200 'WaveA','WaveB','WaveC'..... etc
Prompt xWave, "Enter wave for x values : "
Prompt yWave, "Enter wave for y values: "
DOPrompt "Enter x and y waves", xWave, yWave

Is this correct for picking out two of the created waves, so later in the macro I can graph the two?
Also, is it possible to provide a list of the created waves within the prompt so the user can just pick 2 out?

Thanks,
Cory

Skip loaded columns

Cory K — Wed, 19 Nov 2008 18:50:57 -0600

I am reading in tab-delimited text files using:
LoadWave

Are there any flags I can add to skip columns.
For example if I have columns 0,1,2,3,4,5,6,7,8

But I only want to read in 0,1,4,5,6
What flag would I add?

Plotting only every Nth point

kevin — Wed, 19 Nov 2008 14:19:16 -0600

I'm plotting data as yWave vs. xWave. There are simply too many points displayed. I'd like to only plot every, say, 10th point. But I don't want to delete any of the data.

Also, I use several different yWaves---something like yWave1, yWave2, etc---plotted against the same xWave, so I don't want to have to change the values of xWave.

Thanks,
Kevin

Multiply array by X

Skargaemer — Fri, 14 Nov 2008 12:20:48 -0600

Hi,

I'm not too familiar with IGOR syntax, how would I take a given array and multiply the whole thing by some constant?

Is this close?:
Duplicate wave1, wave2
wave2 = wave1 * 10
Display wave2

Thanks

Force multipeak fitting

yqgao — Mon, 10 Nov 2008 16:32:55 -0600

Hi there, I am new to this program, here we have written a program to calculate peak area of a series spectra in one file ,for example, wave0 to wave 8000, to construct one intensity image, , while we found that there are two peaks so close that general fitting can not recognize these two peaks as one, we can force fit the specific peak range into two peaks, can any one can tell me how to do batch fitting so that we needn't to do so one by one ?
Thanks

Fitting Multiple Curves With Multiple Functions

maxxcw — Sun, 09 Nov 2008 22:42:42 -0600

Here's my problem in principle:

I wish to fit one set of data Energy(x) with the equation a*x+b. At the same time I wish to fit a completely different set of data Charge(x) with the curve a*x^2+b, where a and b are the same in both fits. Is Igor able to fit both of these curves simultaneously by minimizing the summed error from each fit?

Thanks

Multipeak Fit with original negative peaks?

garrison — Mon, 10 Nov 2008 03:54:30 -0600

Dear all,

I am new to Igor Pro and but found it is powerful for signal process. I would like to decompose some characteristic peaks from an experimental measurement. I think the MultiPeak Fit function of Igor Pro should do the job. After several days of trying, I still can't get it works correctly. For example, although it could fit the total curve nicely, but the decomposition, ie. the individual peaks, is not correct.

The experimental data is attached. Could any expert please advice how to utilize MultiPeak Fit and solve the current fit that I can use it an an example to solve many of other measurements.

Thank you very much for your kind help.

Regards,

Run Igor.exe in a VBA Shell to analyze a datafile with a Procedure

kstrieb — Wed, 12 Nov 2008 01:25:07 -0600

I want to automate data processing and plotting with VBA code in an Access App.
I will use an existing Procedure with many datafile (exp.xls)
I am new to Igor....my collegue wrote the procedure.
The following code opens Igor just fine with the procedure loaded, but I need to know how to modify the procedure to get the it to find, load and process the data in exp.xls:
VBA.Shell """C:\Program FIles\WaveMetrics\Igor Pro Folder\Igor.exe""" & Chr(34) & """C:\exp.xls""" & Chr(34), vbNormalFocus

Thanks!

The equations for ExpGauss and ExpConvExp

garrison — Wed, 12 Nov 2008 02:07:56 -0600

Hi there,

Does anyone know what's the explicit equations for the fitting function ExpGauss and ExpConvExp used in Igor Pro?

Thanks

Sum of two Gaussians

English_Lab — Tue, 11 Nov 2008 09:22:44 -0600

I wrote a program that will open up a file and fit the data to a gaussian peak. Some of the new data we're collecting has 2 peaks and I would like to know how to fit a gaussian to each peak. Each of these files contains a large amount of frames, so I want it to be automatic. I already have the code in place to fit a gaussian to each frame and load the coefficients into a separate wave for storage. I just need to know how to code for the 2 gaussian fits. Thanks.

FuncFit Error Flag?

leandract — Mon, 02 Jun 2008 13:12:38 -0500

I am writing a macro that runs through a number of files and fits them to a number of user-defined functions. This all works great except when the function returns an error of

**** Singular matrix error during curve fitting ****

which I know means that the equation has too many parameters and one is ill defined. (I'm fitting single exponentials versus double exponentials).

Unfortunately, this singular matrix error crashes my whole macro, when what I'd really like it to do is to generate an error message (that I can redirect somewhere), and continue with the next fit in the macro. It seems like there should be a flag whose status I can check before the macro crashes so that I can skip over the crash part.
Is this making sense?

Thanks,
-Karen f.

Creating waves of arbitrary data

lizhb — Wed, 05 Nov 2008 17:49:07 -0600

I know how to import data, but I cannot figure out how to create waves of arbitrary data inside Igor using command line functions. For example, if I want to make a wave with the values 0 5 3 -2, how do I do this? Is there a way to create a wave like this, where the values are not a function of the index? I know how to do this by using the GUI to edit the values in a table, but I want to implement this via command line functions, so I can do it in my procedures.

Layout- Arrange window order

patarroyo — Wed, 05 Nov 2008 13:56:26 -0600

Whenever I want to arrange graphs on a layout, I first create the layout and then arrange. I don't use the dialog by itself; instead I send the command to the clipboard where I manually rearrange my graphs so that they appear in the order I desire on the layout. Is there a way to do this within the dialog? Or is my way the only viable workaround?

Killing Graphs From Command Line

patarroyo — Thu, 30 Oct 2008 11:07:32 -0500

I have searched the Web, the Help files, and everywhere in between. I cannot find a way to kill graphs from the command line. It's easy to kill waves, but what about graphs, or even tables? Is there a way to kill these objects from the command line?

Transform Axes Canned Transformations

jjweimer — Wed, 29 Oct 2008 15:47:49 -0500

In a different forum was posted thoughts about Transform Axes as ...

johnweeks wrote:

...Perhaps I should add some canned Arrhenius transformation function.

I think the following two canned transformations for temperature would be useful:

a) oC -> 1/K: 1/(x +273.15)
b) 1/K -> oC: (1/x) - 273.15

BTW, a factor of 1000 is used to adjust the 1/K scale to be in inverse milli-Kelvin (which can also be done using the proper escape codes in the axis label).

(and I meant to append this to the Wish List rather than start a new topic --- my apologies)

Looking for an IGOR Programmer

kmjacobs — Thu, 30 Oct 2008 12:40:31 -0500

I am looking for someone to make slight minor modifications to a Procedure written by Jeremy Bergsman a few years ago. The purpose of the procedure is detection of epileptiform activity (although it could also be used to detect other kinds of activity). We need to add a moving baseline to the detection using filtered data. I know programmers prefer to start from scratch with their own program, but this is already a very nice module. It just needs this one thing - and then there are a couple more things that would be optionally added.
The procedure currently has FFT as an optional detection method. The calculation of the FFT slows down the automated mode, so we would like the option to turn off the calculation/display of the FFT when we are not using it for detection.

Finally, we would like - perhaps even as a separate procedure/module - so this could be started from scratch - a way to output FFT data. We have to thing a little bit more about this - how we would like the output, etc.

I have the means to pay someone to do this programming.

If for some reason you would prefer to view it as a collaboration in order to get your name on a publication, that is also an option.

Please email me at kmjacobs@vcu.edu if you are interested.

Modify mirror axis

warakurna — Thu, 23 Oct 2008 06:18:37 -0500

Hej!

I have a problem with my mirror axis. So normally it displays the same range and values as the original axis. But I want to display the mirrored x-axis computed as: mirrored x-axis = 1000/(X-axis)-273.15

So, I want to put diverse temperature back to T(°C) on the mirrored x-axis without having T(°C) data.
Is there a simple way to do this in Igor?
An example of a plot with the normal mirror axis is attached.

Cheers,
Jan

Unconnect waves in graph

Olav Kiam — Tue, 28 Oct 2008 11:58:52 -0500

To display a number of different waves, I use the AppendToGraph function. See the code to see how. I would like to plot currents (the Y-values) against their voltages (the X-values). The plotmode is set to lines, or lines and markers. This works fine, except for the fact that all the different current waves are connected to the previous one. I would like the individual values of each current wave to be connected, but not the waves themselves to be connected to each other.
I noticed that when I plot every current wave against one single voltage wave (in the same way) I get what I want. However, I really need to plot the current values against their own voltage value.
Is there a way to get what I want?

Olav

Function doThing()
String Xwave = "meanCurrents"
String YWave = "meanVoltages"
String current_waves = "Current"
Variable index = 0
 
String graphicName = "IV_Plot"	
String these_Waves = WaveList(current_waves + "*",";","")
 
do				// for every wave to add
	String /G this_wave = StringFromList(index, these_Waves)
	if (strlen(this_Wave) == 0)
		break
	else
		plotGraph(graphicName, Xwave, Ywave, index)
	endif
 
	index += 1
while(1)
end
 
//####################################################
Function plotGraph(graphName,the_wave, the_xaxis ,i)
 
String graphName
String the_wave
String the_xaxis
Variable i
 
 
if (i ==0)
	display /N=$(graphName) $the_wave vs $the_xaxis
else
	AppendToGraph /W=$(graphName) $the_wave vs $the_xaxis
endif
 
end

Symbolic path already exists

Olav Kiam — Tue, 28 Oct 2008 08:03:29 -0500

Dear Igor users,

The script I am trying to write needs to open all txt files from a folder, load the waves, and calculate some things. It works fine, however, for every file Igor asks me me the following: "The symbolic path datadir already exists. Do you want to change it?" Yes / No.
Since there will be many files, i would rather not be asked this question. Even more because it doesn't seem to matter whether I click yes or no.

Can I prevent this question from popping op every time?

Regards,

Olav

Function processfiles(folder)
 
String folder
NewPath/Q datadir, folder
String fileName
Variable index = 0
 
do fileName = IndexedFile(datadir, index, ".txt")
if(strlen(fileName) == 0)
break
endif
 
loadcsf(folder, fileName)
 
// here I work on the waves
 
end
 
//########################
Function loadcsf(fromthisfolder, thisFile)
 
String fromthisfolder
String thisFile
NewPath/Q datapath, fromthisfolder
 
String columnInfoString = ""
columninfostring + = "N='Time1'; 'N=Current1'; 'N='Voltage1';"
 
loadWave/J /A B=columninfostring /P=datapath /Q thisFile
 
end

Rename Graphwindow from string variable

Olav Kiam — Mon, 27 Oct 2008 13:16:40 -0500

Dear Igor users,

Today I am having some trouble with naming the graph-windows. I would like to be able to give the graph (or window, does it matter?) a name that is stored in a string variable. However, what happens is that the graphwindow gets the literal of that I write after the /N flag (in the code 'graphName' will be the new title). I tried to workaround this with the RenamWindow command, but got the same trouble. See code below.

Is there a way to name the graphs in the way that I want to do?

Function displayGraph(this_wave, x_axis, graphName)

String this_wave
String x_axis
String graphName

Display /N=graphName /L=VertCrossing/B=HorizCrossing $this_wave vs $x_axis;

end

Graph axis in middle of wave-line

Olav Kiam — Sat, 25 Oct 2008 05:10:15 -0500

Dear Igor Users,

Is it possible to put the x-axis and the y-axis on the zero line? This way the graph-line would be something like Current = a*Voltage, and the both axis' would look like a coordinate system, except with different scalings.
If this is possible, how can you do that?

Thanks in advance,

Olav

including erros when fitting

pascal — Thu, 23 Oct 2008 13:57:27 -0500

Hello everyone,

i can't find any way to include my errors (wssr, esd..) when i fit to experimental data. Also, how do i produce error-beams in a graph?
I'm currently coping with four different softwares for fitting, plotting, ... surely igor must be able to do anything sigmaplot or excel or any standard fitting-software can do..?

thanks a lot
pascal

random numbers

VL2008 — Thu, 23 Oct 2008 11:42:53 -0500

Hi,

can Igor generate random numbers? say, gaussian spread around zero mean value or a uniform spread between 0 and whatever value.

or is there any other way to produce noise generator function which i can then loop and every time it is run the result is different (random)

thanks in advance
Slav