The main goal of this notebook is to follow the evolution of a wavefront over time.

The ASCII input data files supported by this notebook are produced by:

This notebook will output an  ASCII file of the edge position according to the selected algorithms.


Select your IPTS


Need help using the IPTS selector?

Select profiles files to process

Using the file selection tool, select the profile files you created.

If you produced the input file using the radial profile notebook, feel free to select all the ASCII files (each corresponding to the radial profile of one single image).  If the input file is coming from the linear profile notebook, only 1 ASCII file can be selected.


UI presentation

Running the next cell will bring the user interface (UI) to life.

Prepare data tab


Make sure you want to perform the calculation on all the files loaded. If you want to exclude any of the files, select the file using the file index slider and turn off the Use this file checkbox.


Step 2

To help the algorithm, select the range of data to use to detect the edge and try to exclude any signal you don’t care.


Step 3

To improve statistics and speed, play with the rebin parameters (size and type). We noticed that in nearly all cases, binning will speed up the algorithms and will help find the right edge.

Edge calculation tab

Once you are done preparing the data, it’s time to detect the edge position. 3 algorithms are available and can be used at the same time to compare the results. Depending on the signal, such or such algorithm may work better than another one.

List of algorithms available

Sliding Average

Check the following document to learn about the algorithm behind it PDF document

Error function

The signal is fitted using a modified version of the error function as shown here

Change point

This algorithm uses the following python library (changepy)


Run algorithms

Select the algorithms you want to use, or click *ALL to use all of them, then click Run Algorithm Selected

Export data

Click the Export … button to create the final ASCII file. Select the output folder and click OK.