# PdfGetXProcessor

`PdfGetXProcessor` is the core numerical task: it feeds the averaged intensity profiles into PDFgetX3 and collects the requested scattering functions.

## Inputs

- `radial`: `numpy.ndarray` describing the scattering axis (Q or r).
- `intensity`: Either a single profile (`ndim == 1`) or a stack of profiles (`ndim == 2`).
- `info`: Metadata dictionary propagated from the averaging stage (`wavelength`, `nb_avg`, etc.).
- `pdfgetx_options`: Prepared `PDFConfig` object (see `PdfGetXConfig`).

## Outputs

- `results`: List of `PDFGetter` instances (one per processed profile). Each instance exposes attributes such as `.iq`, `.sq`, `.fq`, and `.gr`.
- `info`: The same metadata dictionary received as input.
- `pdfgetx_options`: The effective configuration, returned for downstream consumers (e.g. exporters).

## Notes

- `diffpy.pdfgetx` must be installed; otherwise the task raises an informative import error.
- Multiple frames are processed sequentially with a single `PDFGetter` instance whose state is copied after each run.

```python
from ewokspdf.tasks.processor import PdfGetXProcessor

processor = PdfGetXProcessor()
processor(radial=radial_array,
          intensity=intensity_array,
          info=metadata,
          pdfgetx_options=cfg)

results = processor.outputs.results  # list of PDFGetter copies
fq = results[0].fq  # (Q, F(Q)) tuple
```