leoouma/cassini2UTM

A QGIS plugin used to calculate 7-parameter Bursa-Wolf datum shifts from control points and perform coordinate conversions for Cassini-Soldner projections commonly used in Kenya's legacy cadastral data # Cassini Tools (Shift Finder & Coordinate Converter) **Cassini Tools** is a powerful, lightweight QGIS plugin designed for surveyors, GIS professionals, and geodetic engineers who work with legacy **Cassini-Soldner** coordinate reference systems in East Africa. The plugin provides a dual-tabbed graphical interface that solves two critical problems: 1. **Datum Shift Parameter Finder:** Derives a local, highly accurate 7-parameter Helmert/Bursa-Wolf transformation matrix using 4 localized control points. 2. **Batch Coordinate Converter:** Converts massive blocks of coordinate pairs (up to 50+ lines) directly from clipboard layouts (Excel, TSV, CSV) using custom or computed Proj4 strings, eliminating the need to re-project layers or manually script coordinate iterations. --- ## Key Features * **Native QGIS CRS Selection Widgets:** No more hunting down complex EPSG strings or copying raw text parameters. Select your reference and target zones using QGIS’s built-in interactive projection dialog maps. * **Pure NumPy Linear Least-Squares Regression:** Uses an exact, multi-point Bursa-Wolf matrix solver to compute 3 translation vectors ($dX, dY, dZ$), 3 rotational axis angles ($eX, eY, eZ$), and a scale adjustment factor ($ppm$). * **Model Fit Precision Metrics:** Computes the Root Mean Square Error (RMSE) in meters to help you evaluate the geometric quality and integrity of your control points. * **Cross-Tab Workflow Integration:** Calculating a set of shift parameters automatically formats and populates the converter's source profile, allowing a seamless transition from parameter estimation to batch coordinate application. * **Robust Multi-Delimiter Parsing:** The converter accepts space-separated, tab-separated, comma-separated, or semicolon-separated coordinate listings directly. --- ## Installation 1. Locate your active QGIS profile plugin folder. On Windows, this is typically found at: ```text C:\Users\ \AppData\Roaming\QGIS\QGIS3\profiles\default\p …