Data Loader

The DataLoader class handles the import and validation of user-provided data files before they are passed to the application’s visualization and fitting components.

Responsibilities

  • Open files using a dialog or programmatic input
  • Read and validate .csv content
  • Ensure required columns (X, Y) are present
  • Reject malformed or incomplete data
  • Return a clean pandas.DataFrame for downstream use

Supported Formats

Main Methods

load_data(file_name=None)

  • Opens a file dialog (if file_name is not passed)
  • Dispatches to the appropriate read method
  • On success, returns a validated DataFrame and the file path

read_csv(file_path)

  • Uses pandas.read_csv() to load file
  • Validates presence of X and Y columns
  • Checks for NaNs or non-numeric values

show_error_message(message)

  • Uses QMessageBox to inform the user of errors (e.g., missing columns or invalid format)

Typical Integration

df, file_path = data_loader.load_data()
if df is not None:
    tab.load_data_into_tab(df, file_path)

Once the data is loaded:

  • The table view (X/Y Data) is updated
  • The main plot is refreshed
  • Toolbar actions are enabled
  • Fit controls become accessible