CustomMeasurement
This class allows the creation of a new label analysis measurement, based on a user-defined formula.
A custom measurement is defined by a string formula that can invoke other measurements. It can be used by most of the individual analysis algorithms. It must have a unique name.
The formula defining a custom measurement must be written in accordance with the custom formula syntax. The validity of the formula can be verified with the checkMeasurementFormula method.
Notes
A custom measurement is defined by a string formula that can invoke other measurements. It can be used by most of the individual analysis algorithms. It must have a unique name.
The formula defining a custom measurement must be written in accordance with the custom formula syntax. The validity of the formula can be verified with the checkMeasurementFormula method.
Notes
- Even if it generally works, it is not recommended to create a new user measurement which depends on another user measurement, because it may not be as efficient as one might expect. The order of computation may also cause some problems.
- A user-defined measurement cannot refer to an array of another measurement, except for distributions like FeretDiameter where the array is accessed through brackets.
AnalysisMsr::Ptr analysis = std::make_shared< AnalysisMsr >(); // Create a circularity factor between 0 and 1 std::string circularityFormula = "1.0/" + NativeMeasurements::inverseCircularity2d->name(); if ( checkMeasurementFormula( circularityFormula ) ) { const auto* customMeasurementInfo = AnalysisMsr::registerCustomMeasurement( "Circularity", circularityFormula, "This is my circularity factor." ); auto circularity = analysis->select( customMeasurementInfo ); } else std::cerr << "Invalid formula: " << circularityFormula << std::endl;