Base pattern
A base pattern is a 1D diffraction pattern in the chi format. It is typically obtained from software such as DIOPTAS. PeakPo requires users to have a base pattern file to perform further analysis.
To set a base pattern, click the Open button in the base pattern box of the Main tab and select a chi file. For optimal workflow, it's recommended to store the chi, tif, and poni files in the same folder.
When you open a base pattern this way, PeakPo sets the folder containing the base pattern file as the working directory.
Once a base pattern is loaded, you can easily navigate through a large dataset using the navigation buttons in the base pattern box of the Main tab. The step spin box defines the step size for the forward and backward navigation buttons (< and >).
PeakPo also provides buttons to jump to the first and last files of the dataset (|< and >| buttons, respectively). Additionally, you can sort the file list by either file name or timestamp using the radio buttons. For example, selecting the Time radio button will allow you to quickly access the most recent XRD pattern by clicking the >| button.
PeakPo can be slow for several reasons, such as the use of Matplotlib for plotting (which isn't the fastest library) and the time it takes for background subtraction and cake image creation. To speed up navigation through large datasets, PeakPo saves background-subtracted 1D patterns and cake images in a temporary-pkpo folder. This folder is a subdirectory of the folder containing your chi and tif files.
When you open a chi file for the first time, PeakPo may seem slower as it processes background subtraction and cake images, since these files aren't yet available in the temporary folder. However, once you've viewed a chi file, PeakPo can quickly access the preprocessed data from the temporary folder, resulting in faster performance.
This behavior is customizable. If you need to force PeakPo to regenerate the temporary files, you can control this by unchecking specific boxes in the Temporary Files section of the Process tab. Unchecking these boxes will prompt PeakPo to reprocess the necessary files.
In the Main tab, PeakPo provides input fields for adjusting pressure and temperature. The large spin boxes are used to set the pressure and temperature values. The smaller spin boxes below them are for setting step sizes. The buttons next to the step spin boxes serve as shortcuts for frequently used step sizes.