# Powder plot

A powder plot represents the intensity as a function of the q vector, defined as $q=\sqrt{q_{xy}^2+q_z^2}$. This allows for comparison with powder diffractograms obtained from other sources.

## Generate the powder plot

1. **Select the Image**: Choose the merged image of scans 5151 and 5152.
2. **Open LineScan**: Click on the `LINE` icon (LineScan over whole image). This opens the `Powder Plot` window.

## Configure the plot

- **Binning**: Adjust the binning by changing the `number of x-axis data points`. For consistency across comparisons, it’s recommended to leave this setting unchanged.
- **Units**: Choose to display the data as a function of either $q$ or $2\theta$. Selecting $2\theta$ is particularly useful when comparing with powder diffractograms obtained using the Cu K$\rm \alpha$1 X-ray emission line.
- **Data Selection**: Focus on data points with $q_z > 0$ and $q_{xy} < 0$ to:
  - Maintain resolution in $q_{xy}$.
  - Prevent peak splitting if the direct beam isn’t perfectly centered at $q_{xy} = 0$.

![](images/powder-plot-config.png)

## Analyze or export the plot

- **Fitting**: GIDVis provides tools to fit the peak positions. However, you may find it easier to export the data and analyze it using your preferred fitting software.
- **Export Data**:
  1. Click on `File > Export Line Data...`.
  2. Select `Export and Close`.

The exported text file contains the powder plot data in a two-column format, suitable for further analysis.