Load and fit a project¶

Start from a complete project with measured data. It contains the structures, experiments, free parameters and analysis settings that determine the fit.

Load¶

import edi

project = edi.Project.load('path/to/project')

The input may be a project folder, its project.edi, or a project .zip. Invalid or incomplete input raises edi.IoError rather than returning a partially loaded project. Project loading explains what the loader checks.

Inspect the free parameters¶

for parameter in project.free_parameters:
    print(parameter.name, parameter.value, parameter.units)

The project already declares which parameters may vary. Review that choice before fitting; structures and parameters shows how a model parameter exposes its value and free flag.

Fit¶

result = project.analysis.fit()
print(result.rwp)
print(result.reduced_chi_square)

analysis.fit() dispatches according to the fitting mode saved in the project. The shared fitting-mode guide explains the modes and their starting-state policies; the same method runs each declared mode. Scan results have a different shape from single or joint outcomes: use result handling.

Follow progress¶

For a single or joint fit, an optional callback receives each iteration record:

def show_iteration(record):
    print(record)


result = project.analysis.fit(on_iteration=show_iteration)

The facade also supports on_start, scan-specific on_scan_start and on_file_complete, and a should_cancel predicate. Scan callbacks are accepted only for a scan-mode project. These hooks report progress; the model and measured data remain in the project.

Read the result¶

For a powder single or joint fit, inspect Rwp and reduced χ² alongside the pattern, uncertainties and correlations. Read the result explains the returned values. A finished minimization alone does not establish that the structural model is appropriate.

Prepare a report¶

project.report.save_html('result.html')

Save the updated project¶

project.save_as('fitted-project')

save_as() puts the project in the new folder and makes that its location for later saves. A Python single or joint fit does not automatically save your project. Scan analysis also writes its progress results during the run; retain the input project separately when you need its initial state.

Open the saved result in the application to inspect it visually, or run the project through the Command line.