def DTR_calculation(arr1, arr2, fill_val1=None, fill_val2=None):
'''
Calculates the DTR indice: mean of daily temperature range.
:param arr1: daily max temperature (e.g. "tasmax")
:type arr1: numpy.ndarray (3D) or numpy.ma.MaskedArray (3D)
:param arr2: daily min temperature (e.g. "tasmin")
:type arr2: numpy.ndarray (3D) or numpy.ma.MaskedArray (3D)
:param fill_val1: fill value of arr1
:type fill_val1: float
:param fill_val2: fill value of arr2
:type fill_val2: float
:rtype: numpy.ndarray (2D) (if "arr1" and "arr2" are numpy.ndarray)
or numpy.ma.MaskedArray (2D) (if "arr1" and "arr2" are numpy.ma.MaskedArray)
.. warning:: "arr1" and "arr2" must be the same type, shape and correspond to the same time step vector.
'''
#.. warning:: If "arr1" and "arr2" are masked arrays, the parameters "fill_val1" and "fill_val2" are ignored, because they have no sense in this case.
arr1_masked = calc.get_masked_arr(arr1, fill_val1)
arr2_masked = calc.get_masked_arr(arr2, fill_val2)
range_ = arr1_masked - arr2_masked # masked array with fill_value = fill_value of the first masked array in expression (i.e. arr1_masked)
DTR = range_.mean(axis=0) # masked array with new fill_value
numpy.ma.set_fill_value(DTR, arr1_masked.fill_value) # we set a fill_value = fill_value of arr1_masked (or arr2_masked)
if not isinstance(arr1, numpy.ma.MaskedArray) : #�or if not isinstance(arr2, numpy.ma.MaskedArray) [because the both input arrays are the same type]
DTR = DTR.filled(fill_value=arr1_masked.fill_value)
return DTR
def GD4_calculation(arr, fill_val=None, threshold=4):
"""
Calculates the GD4 indice: growing degree days (sum of daily mean temperature > 4 degrees Celsius).
:param arr: daily mean temperature (e.g. "tas") in Kelvin
:type arr: numpy.ndarray (3D) or numpy.ma.MaskedArray (3D)
:param fill_val: fill value
:type fill_val: float
:rtype: numpy.ndarray (2D) (if "arr" is numpy.ndarray)
or numpy.ma.MaskedArray (2D) (if "arr" is numpy.ma.MaskedArray)
.. warning:: Units of "arr" must be Kelvin.
.. warning:: If "arr" is a masked array, the parameter "fill_val" is ignored, because it has no sense in this case.
"""
T = threshold + 273.15 # Celsius -> Kelvin
arr_masked = calc.get_masked_arr(arr, fill_val)
new_mask = arr_masked <= T
new_arr_masked = numpy.ma.array(
arr_masked, mask=new_mask, fill_value=arr_masked.fill_value
) # we masked the temperatures <= 4 C
GD4 = new_arr_masked.sum(axis=0)
numpy.ma.set_fill_value(GD4, arr_masked.fill_value)
if not isinstance(arr, numpy.ma.MaskedArray):
GD4 = GD4.filled(fill_value=arr_masked.fill_value)
return GD4
def HD17_calculation(arr, fill_val=None, threshold=17):
"""
Calculates the HD17 indice: heating degree days (sum of (17 degrees Celsius - daily mean temperature)).
:param arr: daily mean temperature (e.g. "tas") in Kelvin
:type arr: numpy.ndarray (3D) or numpy.ma.MaskedArray (3D)
:param fill_val: fill value
:type fill_val: float
:rtype: numpy.ndarray (2D) (if "arr" is numpy.ndarray)
or numpy.ma.MaskedArray (2D) (if "arr" is numpy.ma.MaskedArray)
.. warning:: Units of "arr" must be Kelvin.
.. warning:: If "arr" is a masked array, the parameter "fill_val" is ignored, because it has no sense in this case.
"""
T = threshold + 273.15 # Celsius -> Kelvin
arr_masked = calc.get_masked_arr(arr, fill_val)
a = T - arr_masked
a[a < 0] = 0 # we set to zero values < 0
HD17 = a.sum(axis=0)
numpy.ma.set_fill_value(HD17, arr_masked.fill_value)
if not isinstance(arr, numpy.ma.MaskedArray):
HD17 = HD17.filled(fill_value=arr_masked.fill_value)
return HD17
def vDTR_calculation(arr1, arr2, fill_val1=None, fill_val2=None):
"""
Calculates the vDTR indice: mean absolute day-to-day difference in DTR.
:param arr1: daily max temperature (e.g. "tasmax")
:type arr1: numpy.ndarray (3D) or numpy.ma.MaskedArray (3D)
:param arr2: daily min temperature (e.g. "tasmin")
:type arr2: numpy.ndarray (3D) or numpy.ma.MaskedArray (3D)
:param fill_val1: fill value of arr1
:type fill_val1: float
:param fill_val2: fill value of arr2
:type fill_val2: float
:rtype: numpy.ndarray (2D) (if "arr1" and "arr2" are numpy.ndarray)
or numpy.ma.MaskedArray (2D) (if "arr1" and "arr2" are numpy.ma.MaskedArray)
.. warning:: If "arr1" and "arr2" are masked arrays, the parameters "fill_val1" and "fill_val2" are ignored, because they have no sense in this case.
.. warning:: "arr1" and "arr2" must be the same type, shape and correspond to the same time step vector.
"""
arr1_masked = calc.get_masked_arr(arr1, fill_val1)
arr2_masked = calc.get_masked_arr(arr2, fill_val2)
a = arr1_masked[1:] - arr2_masked[1:]
b = arr1_masked[:-1] - arr2_masked[:-1]
c = abs(a - b)
vDTR = c.mean(axis=0)
numpy.ma.set_fill_value(vDTR, arr1_masked.fill_value)
if not isinstance(arr1, numpy.ma.MaskedArray):
vDTR = vDTR.filled(fill_value=arr1_masked.fill_value)
return vDTR
def ETR_calculation(arr1, arr2, fill_val1=None, fill_val2=None):
"""
Calculates the ETR indice: intra-period extreme temperature range.
:param arr1: daily max temperature (e.g. "tasmax")
:type arr1: numpy.ndarray (3D) or numpy.ma.MaskedArray (3D)
:param arr2: daily min temperature (e.g. "tasmin")
:type arr2: numpy.ndarray (3D) or numpy.ma.MaskedArray (3D)
:param fill_val1: fill value of arr1
:type fill_val1: float
:param fill_val2: fill value of arr2
:type fill_val2: float
:rtype: numpy.ndarray (2D) (if "arr1" and "arr2" are numpy.ndarray)
or numpy.ma.MaskedArray (2D) (if "arr1" and "arr2" are numpy.ma.MaskedArray)
.. warning:: If "arr1" and "arr2" are masked arrays, the parameters "fill_val1" and "fill_val2" are ignored, because they have no sense in this case.
.. warning:: "arr1" and "arr2" must be the same type, shape and correspond to the same time step vector.
"""
arr1_masked = calc.get_masked_arr(arr1, fill_val1)
arr2_masked = calc.get_masked_arr(arr2, fill_val2)
max_arr1_masked = arr1_masked.max(axis=0) # masked array with new fill_value (default)
min_arr2_masked = arr2_masked.min(axis=0) # masked array with new fill_value (default)
ETR = max_arr1_masked - min_arr2_masked # masked array with new fill_value (default)
numpy.ma.set_fill_value(ETR, arr1_masked.fill_value)
if not isinstance(arr1, numpy.ma.MaskedArray):
ETR = ETR.filled(fill_value=arr1_masked.fill_value)
return ETR
