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Since about version 1.3.4 I've noticed a problem when I use a template for event detection (variable amplitude template). After I run event detection axograph seem's to forget the template I defined previously. So every time I run event detection I have to redefine the template. This didn't happen previously.

Thnaks, Chris

Hi,
Thanks for getting back to me so fast.
I just installed QuickTime & from the OSX Installer.
I'm still having the same issue (Axograph crashes when I try to copy). I tried it with Axograph 1.3.3 and 1.3.5.

Anything else I might be able to try?

Thanks again.

The Snow Leopard installer DVD includes a folder named 'Optional Installs', and inside that folder is an installer package named 'Optional Installs.mpkg'. I suggest that you run that installer (specifically install QuickTime 7), as it adds some backward compatibility features that may help AxoGraph copy graphs to the clipboard.

If you're curious, here's some background technical information about the problem: AxoGraph uses the old 'PICT' graphics format for drawing to the screen and clipboard. Apple are slowly phasing out this graphics standard. AxoGraph is currently being rewritten (a huge job) to utilize the Qt 4 cross-platform framework. One of the many advantages of this rewrite will be a switch to Apple's standard graphic format for screen and clipboard (PDF). This should eliminate the backward compatibility problems experienced on the latest versions of OS X 10.6. It will also improve copy and paste of text from the AxoGraph Log window, and spreadsheet windows. However the rewrite is not expected to be complete and tested until later this year.

John.

Hi,
I've been having problems copying graphs. Axograph crashes when I try to copy a graph.
This has only been happening on our Macs running OSX 10.6.
I tried upgrading to the most recent version of Axograph, but that didn't work.
I also tried downgrading to Axograph 1.3.3 (since I saw that update specifically mentions a fix to issues with copying).

Is there anything else that you suggest I try?

Thanks

Hi Bailey,

I've checked on the mean() function, and all is working correctly. Perhaps there's been a small misunderstanding. The mean() function takes an array followed by two optional parameters - the first and last array 'index' over which to calculate the mean. If you are using the C programming language (the default) the index range starts from zero.

Here's the details of the text I ran...

Launch AxoGraph and select File -> New to create a new graph window (number 2). Execute the following lines of C code....

....

int frontWindow = 2;
int frontTrace = 1;
int ZeroTraceRangeMinArrayIndex = 0;
int ZeroTraceRangeMaxArrayIndex = 99;
double y[0];
 
y = yData(frontWindow, frontTrace);
print( "\nBaseline average = ", mean ( y , ZeroTraceRangeMinArrayIndex, ZeroTraceRangeMaxArrayIndex ) * 1000, " mV" );

....

Note the index range 0 to 99 corresponds to the time range 0.1 to 10 ms. The output is....

Baseline average = -0.0449464  mV

Now bring the graph window to the front and select 'Analyze -> Cursor Measure'. Select 'Average Amplitude' and set the range from 0.1 to 10 ms.


AxoGraph - 1 :  Measure Average Amplitude
Volts (mV)
-0.0449464

So the mean() function is working correctly assuming you give it the appropriate index range.

Another suggestion would be to use the yRange() function (or eRange() function) to access the baseline data. When you call these functions, you specify the time range you are interested in (instead of the index range), which is generally easier to work with. So the example code above becomes...

....

int frontWindow = 2;
int frontTrace = 1;
double ZeroTraceRangeMinTime_ms = 0;
double ZeroTraceRangeMaxTime_ms = 10;
double y[0];
 
y = yRange(frontWindow, frontTrace, ZeroTraceRangeMinTime_ms * 0.001, ZeroTraceRangeMaxTime_ms * 0.001 );
print( "\nBaseline average = ", mean ( y ) * 1000, " mV" );


Baseline average = -0.0449464  mV

....

Hope this helps,

John.

In the process of writing an analysis script I decided to include a simple baseline subtraction by averaging and then subtracting a range from the yData. Calling av () or (mean (yData(frontWindow, episode), d_ZeroTraceRangeMin, d_ZeroTraceRangeMax) I get something close but not correct. If I run the builtin subtract baseline I get a true zero. At the moment this isn't a serious problem but I do not understand why I am not getting a good average. I do not believe that the issue is a rounding one, as if I run the accurate built in baseline subtraction first then my own, it comes up with an average other than 0 for the same range.

Thanks very much! I don't know how I missed it.

Resampling is available in AxoGraph under the 'Utilities' menu, 'Graph Utilities' submenu.

There are two options: 'Decimate' for reducing the sample rate, or 'interpolate' for increasing the sample rate.

When decimating, AxoGraph gives you the option of replacing 'N' samples with the average of those samples. This has the effect of reducing noise in the resampled graph.

Hope this helps,

John.

Hi,
Is there a way to resample data?
For example, I collected a continuous data trace at 20 kHz for several minutes. However, for one specific analysis I want data this same data sampled at 1 kHz.

Any suggestions?

Thanks

John, 

Here is another problem with Chart. Whenever I run consecutive Charts, I always get the message that I "Need to open a new Chart Window because the telegraphed gain has changed", even though the gain hasn't changed. This also happens with Preview Chart.

Terry