Source code for ocgis.calc.library.thresholds

import numpy as np

from ocgis.calc import base


class Between(base.AbstractUnivariateSetFunction, base.AbstractParameterizedFunction):
    description = 'Count of values falling within the limits lower and upper (inclusive).'
    parms_definition = {'lower': float, 'upper': float}
    dtype_default = 'int'
    key = 'between'
    standard_name = 'between'
    long_name = 'between'

    def calculate(self, values, lower=None, upper=None):
        """
        :param lower: The lower value of the range.
        :type lower: float
        :param upper: The upper value of the range.
        :type upper: float
        """

        assert (lower <= upper)
        idx = (values >= float(lower)) * (values <= float(upper))
        return np.ma.sum(idx, axis=0)


class Threshold(base.AbstractUnivariateSetFunction, base.AbstractParameterizedFunction):
    description = 'Count of values where the logical operation returns TRUE.'
    parms_definition = {'threshold': float, 'operation': str}
    dtype_default = 'int'
    key = 'threshold'
    standard_name = 'threshold'
    long_name = 'threshold'
    parms_required = ('threshold', 'operation')

    def calculate(self, values, threshold=None, operation=None):
        """
        :param threshold: The threshold value to use for the logical operation.
        :type threshold: float
        :param operation: The logical operation. One of 'gt','gte','lt', or 'lte'.
        :type operation: str
        """

        # perform requested logical operation
        if operation == 'gt':
            idx = values > threshold
        elif operation == 'lt':
            idx = values < threshold
        elif operation == 'gte':
            idx = values >= threshold
        elif operation == 'lte':
            idx = values <= threshold
        else:
            raise NotImplementedError

        ret = np.ma.sum(idx, axis=0)
        return ret

    def _aggregate_spatial_(self, values, weights):
        return np.ma.sum(values)