h5_mahe

HydroErr.HydroErr.h5_mahe(simulated_array: ndarray[tuple[Any, ...], dtype[floating | integer]] | Sequence[int | float], observed_array: ndarray[tuple[Any, ...], dtype[floating | integer]] | Sequence[int | float], replace_nan: float | None = None, replace_inf: float | None = None, remove_neg: bool = False, remove_zero: bool = False) → floating[Any]

Compute the H5 mean absolute error.

\[H_5 = \frac{S_i - O_i}{\left [ \frac {1}{2} \left ( O_i^{-1} + S_i^{-1} \right ) \right ]^{-1}}\]

\[\text{Absolute H Error} =\frac {1}{n}\sum_{i=1}^{n} |H|\]

Range:

Notes:

Parameters:

• simulated_array – An array of simulated data from the time series.

• observed_array – An array of observed data from the time series.

• replace_nan – If given, indicates which value to replace NaN values with in the two arrays. If None, when a NaN value is found at the i-th position in the observed OR simulated array, the i-th value of the observed and simulated array are removed before the computation.

• replace_inf – If given, indicates which value to replace Inf values with in the two arrays. If None, when an inf value is found at the i-th position in the observed OR simulated array, the i-th value of the observed and simulated array are removed before the computation.

• remove_neg – If True, when a negative value is found at the i-th position in the observed OR simulated array, the i-th value of the observed AND simulated array are removed before the computation.

• remove_zero – If true, when a zero value is found at the i-th position in the observed OR simulated array, the i-th value of the observed AND simulated array are removed before the computation.

Return type:

The mean absolute H5 error.

Examples

>>> import HydroErr as he
>>> import numpy as np

>>> sim = np.array([5, 7, 9, 2, 4.5, 6.7])
>>> obs = np.array([4.7, 6, 10, 2.5, 4, 7])
>>> he.h5_mahe(sim, obs)
0.11818409010335018

References

• Tornquist, L., Vartia, P., Vartia, Y.O., 1985. How Should Relative Changes be Measured? The American Statistician 43-46.