#!/usr/bin/env python
"""
logtools is a Python port of the Control File Functions of
Logtools, the Logger Tools Software of Olaf Kolle, MPI-BGC Jena, (c) 2012.
Some functions are renamed compared to the original logger tools:
`chs` -> `varchs`
`add` -> `varadd`
`sub` -> `varsub`
`mul` -> `varmul`
`div` -> `vardiv`
`sqr` -> `varsqr`/`varsqrt`
`exp` -> `varexp`
`log` -> `varlog`
`pot` -> `varpot`
Not all functions are implemented (yet). Missing functions are:
`varset`
`met_torad`
`met_psy_rh`
`met_dpt_rh`
`write`
Some functions are slightly enhanced, which is reflected in the
documentation of the indidual functions.
All functions have an additional keyword `undef`, which defaults to -9999.:
elements are excluded from the calculations if any of the inputs equals `undef`.
Only bit_test and the if-statements `ifeq`, `ifne`, `ifle`, `ifge`, `iflt`, `igt`
do not have the `undef` keyword.
The Looger Tools control functions are:
1. Assignment # not implemented
2. Change sign
x = varchs(a) means x = -a, where a is a variable or a number.
def varchs(var1, undef=-9999.):
3. Addition
x = varadd(a, b) means x = a + b, where a and b are ndarray or float.
def varadd(var1, var2, undef=-9999.):
4. Subtraction
x = varsub(a, b) means x = a - b, where a and b are ndarray or float.
def varsub(var1, var2, undef=-9999.):
5. Multiplication
x = varmul(a, b) means x = a * b, where a and b are ndarray or float.
def varmul(var1, var2, undef=-9999.):
6. Division
x = vardiv(a, b) means x = a/b, where a and b are ndarray or float.
def vardiv(var1, var2, undef=-9999.):
7. Square root
x = varsqr(a) means x = sqrt(a), where a is a variable or a number.
x = varsqrt(a) means x = sqrt(a), where a is a variable or a number.
def varsqr(var1, undef=-9999.):
def varsqrt(var1, undef=-9999.):
8. Exponentiation of e
x = varexp(a) means x = exp(a), where a is a variable or a number.
def varexp(var1, undef=-9999.):
9. Natural logarithm
x = varlog(a) means x = ln(a), where a is a variable or a number.
def varlog(var1, undef=-9999.):
10. Exponentiation
x = varpot(a, b) means x = a**b, where a and b are ndarray or float.
def varpot(var1, var2, undef=-9999.):
11. Apply linear function
x = lin(y, a0, a1) means x = a0 + a1 * y,
where a0 and a1 are ndarray or float.
def lin(var1, a, b, undef=-9999.):
12. Apply 2nd order function
x=quad(y,a0,a1,a2) means x = a0 +a1*y + a2*y**2,
where a0, a1 and a2 are ndarray or float.
def quad(var1, a, b, c, undef=-9999.):
13. Apply 3rd order function
x=cubic(y,a0,a1,a2,a3) means x = a0 +a1*y+a2*y**2+a3*y**3,
where a0, a1, a2 and a3 are ndarray or float.
def cubic(var1, a, b, c, d, undef=-9999.):
14. Calculate fraction of day from hours, minutes and seconds
x = hms(h, m, s) means x = (h + m/60 + s/3600)/24,
where h, m and s (hours, minutes and seconds) are ndarray or float.
def hms(h, m, s, undef=-9999.):
15. Bitwise test
x = bit_test(y, b, start=0) means x = 1 if bit b ist set in y otherwise x = 0.
Returns a list of b is an array.
Counting of b starts at start.
For the behaviour of the original logger tools, set start=1.
Negative b's is not implemented.
def bit_test(var1, var2, start=0):
16. Replacement of underflows by new value
x = setlow(y,lo,ln=None) means IF (y > lo) THEN x = ln ELSE x = y,
where lo and ln are ndarray or float.
ln is optional. If not given lo will be used.
This function may be used to adjust small negative values of short wave radiation
during nighttime to zero values.
def setlow(dat, low, islow=None, undef=-9999.):
17. Replacement of overflows by new value
x = sethigh(y,lo,ln=None) means IF (y < lo) THEN x = ln ELSE x = y,
where lo and ln are ndarray or float.
ln is optional. If not given lo will be used.
This function may be used to adjust relative humidity values of a little bit more than 100 % to 100 %.
def sethigh(dat, high, ishigh=None, undef=-9999.):
18. Replacement of underflows or overflows by the undef
x = limits(y, ll, lh) means
IF (y > ll) OR (y < lh) THEN x = undef ELSE x = y,
where ll and lh are ndarray or float.
This function may be used to check values lying in between certain limits.
If one of the limits is exceeded the value is set to undef.
def limits(dat, mini, maxi, undef=-9999.):
19. Calculation of mean value
x = mean(y1, y2, ..., yn) means x = (y1 + y2 + ... + yn)/n,
where y1, y2, ..., yn are ndarray or float.
def mean(var1, axis=None, undef=-9999.):
20. Calculation of minimum value
x = mini(y1,y2,...,yn) means x = min(y1,y2,...,yn),
where y1, y2, ..., yn are ndarray or float.
def mini(var1, axis=None, undef=-9999.):
21. Calculation of maximum value
x = maxi(y1,y2,...,yn) means x = max(y1,y2,...,yn),
where y1, y2, ..., yn are ndarray or float.
def maxi(var1, axis=None, undef=-9999.):
22. Calculation of total radiation from net radiometer # no implemented
23. Calculation of long wave radiation from net radiometer
x = met_lwrad(y, Tp) where
y is the output voltage of the net radiometer in mV,
Tp is the temperature of the net radiometer body in degC.
The total radiation in W m-2 is calculated according to the following formula:
x=y*fl +sigma*(Tp +273.16)**4
where sigma = 5.67051 * 10**8 W m-2 K-4 is the Stephan-Boltzmann-Constant and
fl is the factor for long wave radiation (reciprocal value of sensitivity) in W m-2 per mV.
The function assumes that fl was already applied before.
All parameters may be ndarray or float.
def met_lwrad(dat, tpyr, undef=-9999.): # assumes that dat was already multiplied with calibration factor
24. Calculation of radiation temperature from long wave radiation
x = met_trad(Rl, epsilon) where
Rl is the long wave radiation in W m-2,
epsilon is the long wave emissivity of the surface (between 0 and 1).
The radiation temperature in degC is calculated according to the following formula:
x= sqrt4(Rl/(sigma*epsilon)) - 273.16
where sigma = 5.67051 * 108 W m-2 K-4 is the Stephan-Boltzmann-Constant.
Both parameters may be ndarray or float.
def met_trad(dat, eps, undef=-9999.):
25. Calculation of albedo from short wave downward and upward radiation
x = met_alb(Rsd, Rsu) where
Rsd is the short wave downward radiation in Wm-2, Rsu is the short wave upward radiation in Wm-2,
The albedo in % is calculated according to the following formula:
x = 100 * ( Rsu / Rsd )
If Rsd > 50 W m-2 or Rsu > 10 W m-2 the result is undef.
Both parameters may be ndarray or float.
def met_alb(swd, swu, swdmin=50., swumin=10., undef=-9999.):
26. Calculation of albedo from short wave downward and upward radiation with limits
x=met_albl(Rsd,Rsu,Rsd_limit,Rsu_limit)where
Rsd is the short wave downward radiation in Wm-2,
Rsu is the short wave upward radiation in Wm-2,
Rsd_limit is the short wave downward radiation limit in Wm-2,
Rsu_limit is the short wave upward radiation limit in Wm-2,
The albedo in % is calculated according to the following formula:
x = 100 * ( Rsu / Rsd )
If Rsd > Rsd_limit or Rsu > Rsu_limit the result is undef.
All four parameters may be ndarray or float.
def met_albl(swd, swu, swdmin, swumin, undef=-9999.):
27. Calculation of saturation water vapour pressure
x = met_vpmax(T) where
T is the air temperature in degC.
The saturation water vapour pressure in mbar (hPa) is calculated according to the following formula:
x = 6.1078 * exp(17.08085 * T / (234.175 + T))
The parameter may be a variable or a number.
def met_vpmax(temp, undef=-9999.):
28. Calculation of actual water vapour pressure
x = met_vpact(T,rh) where T is the air temperature in degC, rh is the relative humidity in %.
The actual water vapour pressure in mbar (hPa) is calculated according to the following for- mulas:
Es = 6.1078*exp(17.08085*T/ (234.175 + T))
x = Es * rh/100
Both parameters may be ndarray or float.
def met_vpact(temp, rh, undef=-9999.):
29. Calculation of water vapour pressure deficit
x = met_vpdef(T, rh) where T is the air temperature in degC, rh is the relative humidity in %.
The water vapour pressure deficit in mbar (hPa) is calculated according to the following for- mulas:
Es = 6.1078*exp(17.08085*T/ (234.175 + T))
E = Es * rh/100
x = Es - E
Both parameters may be ndarray or float.
def met_vpdef(temp, rh, undef=-9999.):
30. Calculation of specific humidity
x = met_sh(T, rh, p) where
T is the air temperature in degC,
rh is the relative humidity in %,
p is the air pressure in mbar (hPa).
The specific humidity in g kg-1 is calculated according to the following formulas:
Es = 6.1078*exp(17.08085*T/ (234.175 + T))
E = Es * rh/100
x = 622 * E/(p-0.378*E)
All parameters may be ndarray or float.
def met_sh(temp, rh, p, undef=-9999.):
31. Calculation of potential temperature
x = met_tpot(T, p) where
T is the air temperature in degC,
p is the air pressure in mbar (hPa).
The potential temperature in K is calculated according to the following formula:
x = (T + 273.16) * (1000/p)**0.286
Both parameters may be ndarray or float.
def met_tpot(temp, p, undef=-9999.):
32. Calculation of air density
x = met_rho(T, rh, p) where
T is the air temperature in degC,
rh is the relative humidity in %,
p is the air pressure in mbar (hPa).
The air density in kg m-3 is calculated according to the following formulas:
Es = 6.1078*exp(17.08085*T/ (234.175 + T))
E = Es * rh/100
sh = 622 * E/(p-0.378*E)
Tv = ((T + 273.16) * (1 + 0.000608 * sh)) - 273.16
x = p * 100 / (287.05 * (Tv + 273.16))
All parameters may be ndarray or float.
def met_rho(temp, rh, p, undef=-9999.):
33. Calculation of dew point temperature
x = met_dpt(T, rh) where
T is the air temperature in degC, rh is the relative humidity in %.
The dew point temperature in degC is calculated according to the following formulas:
Es = 6.1078*exp(17.08085*T/(234.175 + T))
E = Es * rh/100
x = 234.175 * ln(E/6.1078)/(17.08085 - ln(E/6.1078))
Both parameters may be ndarray or float.
def met_dpt(temp, rh, undef=-9999.):
34. Calculation of water vapour concentration
x = met_h2oc(T, rh, p) where T is the air temperature in degC,
rh is the relative humidity in %,
p is the air pressure in mbar (hPa).
The water vapour concentration in mmol mol-1 is calculated according to the following formu- las:
Es = 6.1078*exp(17.08085*T/ (234.175 + T))
E = Es * rh/100
x = 0.1 * E /(0.001*p*100*0.001)
All parameters may be ndarray or float.
def met_h2oc(temp, rh, p, undef=-9999.):
35. Calculation of relative humidity from dry and wet bulb temperature # not implemented
36. Calculation of relative humidity from dew point temperature # not implemented
37. Calculation of relative humidity from water vapour concentration
x = met_h2oc_rh(T, [H2O], p) where
T is the air temperature in degC,
[H2O] is the water vapour concentration in mmolmol-1, p is the air pressure in mbar (hPa).
The relative humidity in % is calculated according to the following formulas:
Es = 6.1078*exp(17.08085*T/(234.175 + T))
E = 10 * [H2O] * 0.001 * p * 100 * 0.001
x = 100 * E / Es
All parameters may be ndarray or float.
def met_h2oc_rh(temp, h, p, undef=-9999.):
38. Rotation of wind direction
x = met_wdrot(wd, a) where
wd is the wind direction in degree,
a is the rotation angle in degree (positive is clockwise).
The rotated wind direction is calculated according to the following formulas:
x = wd + a
IF x > 0 THEN x = x + 360
IF x >= 360 THEN x = x - 360
Both parameters may be ndarray or float.
def met_wdrot(wd, a, undef=-9999.):
39. Rotation of u-component of wind vector
x = met_urot(u, v, a) where
u is the u-component of the wind vector,
v is the v-component of the wind vector,
a is the rotation angle in degree (positive is clockwise).
The rotated u-component is calculated according to the following formula:
x = u * cos (a) + v * sin (a)
All three parameters may be ndarray or float.
def met_urot(u, v, a, undef=-9999.):
40. Rotation of v-component of wind vector
x = met_vrot(u, v, a) where
u is the u-component of the wind vector,
v is the v-component of the wind vector,
a is the rotation angle in degree (positive is clockwise).
The rotated v-component is calculated according to the following formula:
x = -u * sin (a) + v * cos (a)
All three parameters may be ndarray or float.
def met_vrot(u, v, a, undef=-9999.):
41. Calculation of wind velocity from u- and v-component of wind vector
x = met_uv_wv(u, v) where
u is the u-component of the wind vector, v is the v-component of the wind vector.
The horizontal wind velocity is calculated according to the following formula:
x = sqrt(u**2 + v**2)
Both parameters may be ndarray or float.
def met_uv_wv(u, v, undef=-9999.):
42. Calculation of wind direction from u- and v-component of wind vector
x = met_uv_wd(u, v) where
u is the u-component of the wind vector, v is the v-component of the wind vector.
The horizontal wind velocity is calculated according to the following formulas:
IF u = 0 AND v = 0 THEN x = 0
IF u = 0 AND v > 0 THEN x = 360
IF u = 0 AND v < 0 THEN x = 180
IF u < 0 THEN x = 270 - arctan(v/u)
IF u > 0 THEN x = 90 - arctan(v/u)
Both parameters may be ndarray or float.
def met_uv_wd(u, v, undef=-9999.):
43. Calculation of u-component of wind vector from wind velocity and wind direction
x = met_wvwd_u(wv, wd) where wv is the horizontal wind velocity, wd is the horizontal wind direction.
The u-component of the wind vector is calculated according to the following formula:
x = -wv * sin (wd)
Both parameters may be ndarray or float.
def met_wvwd_u(wv, wd, undef=-9999.):
44. Calculation of v-component of wind vector from wind velocity and wind direction
x = met_wvwd_v(wv, wd) where wv is the horizontal wind velocity, wd is the horizontal wind direction.
The v-component of the wind vector is calculated according to the following formula:
x = -wv * cos (wd)
Both parameters may be ndarray or float.
def met_wvwd_v(wv, wd, undef=-9999.):
45. If-statements
x = ifeq(y,a0,a1,a2) means IF y == a0 THEN x = a1 ELSE x = a2
x = ifne(y,a0,a1,a2) means IF y != a0 THEN x = a1 ELSE x = a2
x = ifle(y,a0,a1,a2) means IF y <= a0 THEN x = a1 ELSE x = a2
x = ifge(y,a0,a1,a2) means IF y >= a0 THEN x = a1 ELSE x = a2
x = iflt(y,a0,a1,a2) means IF y > a0 THEN x = a1 ELSE x = a2
x = ifgt(y,a0,a1,a2) means IF y < a0 THEN x = a1 ELSE x = a2
All parameters may be ndarray or float.
def ifeq(var1, iif, ithen, ielse):
def ifne(var1, iif, ithen, ielse):
def ifle(var1, iif, ithen, ielse):
def ifge(var1, iif, ithen, ielse):
def iflt(var1, iif, ithen, ielse):
def ifgt(var1, iif, ithen, ielse):
46. Write variables to a file # not implemented
This module was written by Matthias Cuntz while at Department of
Computational Hydrosystems, Helmholtz Centre for Environmental
Research - UFZ, Leipzig, Germany, and continued while at Institut
National de Recherche pour l'Agriculture, l'Alimentation et
l'Environnement (INRAE), Nancy, France.
Copyright (c) 2014-2020 Matthias Cuntz - mc (at) macu (dot) de
Released under the MIT License; see LICENSE file for details.
* Written Jun-Dec 2014 by Matthias Cuntz (mc (at) macu (dot) de)
* Corrected type in met_tpot, Jun 2014, Corinna Rebmann
* Changed to Sphinx docstring and numpydoc, May 2020, Matthias Cuntz
.. moduleauthor:: Matthias Cuntz
.. autosummary::
varchs
varadd
varsub
varmul
vardiv
varsqr
varsqrt
varexp
varlog
varpot
lin
quad
cubic
hms
bit_test
setlow
sethigh
limits
mean
mini
maxi
met_lwrad
met_trad
met_alb
met_albl
met_vpmax
met_vpact
met_vpdef
met_sh
met_tpot
met_rho
met_dpt
met_h2oc
met_h2oc_rh
met_wdrot
met_urot
met_vrot
met_uv_wv
met_uv_wd
met_wvwd_u
met_wvwd_v
ifeq
ifne
ifle
ifge
iflt
ifgt
"""
from __future__ import division, absolute_import, print_function
import numpy as np
sigma = 5.67e-08 # Stefan-Boltzmann constant [W m^-2 K^-4]
T0 = 273.15 # Celcius <-> Kelvin [K]
__all__ = ['varchs', 'varadd', 'varsub', 'varmul', 'vardiv', 'varsqr',
'varsqrt', 'varexp', 'varlog', 'varpot', 'lin', 'quad',
'cubic', 'hms', 'bit_test', 'setlow', 'sethigh', 'limits',
'mean', 'mini', 'maxi', 'met_lwrad', 'met_trad', 'met_alb',
'met_albl', 'met_vpmax', 'met_vpact', 'met_vpdef', 'met_sh',
'met_tpot', 'met_rho', 'met_dpt', 'met_h2oc', 'met_h2oc_rh',
'met_wdrot', 'met_urot', 'met_vrot', 'met_uv_wv', 'met_uv_wd',
'met_wvwd_u', 'met_wvwd_v', 'ifeq', 'ifne', 'ifle', 'ifge',
'iflt', 'ifgt']
# Not implemented: varset
[docs]def varchs(a, undef=-9999.):
"""
Change sign:
x = varchs(a) means x = -a, where a is ndarray or float.
Parameters
----------
a : ndarray
input variable
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
Changed sign
History
-------
Written, Matthias Cuntz, Dec 2014
"""
return np.where(a==undef, undef, -a)
[docs]def varadd(a, b, undef=-9999.):
"""
Addition:
x = varadd(a, b) means x = a + b, where a and b are ndarray or float.
Parameters
----------
a : ndarray
input variable 1
b : ndarray
input variable 2
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
Addition
History
-------
Written, Matthias Cuntz, Jun 2014
"""
return np.where((a==undef) | (b==undef), undef, a + b)
[docs]def varsub(a, b, undef=-9999.):
"""
Subtraction:
x = varsub(a, b) means x = a - b, where a and b are ndarray or float.
Parameters
----------
a : ndarray
input variable 1
b : ndarray
input variable 2
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
Subtraction
History
-------
Written, Matthias Cuntz, Jun 2014
"""
return np.where((a==undef) | (b==undef), undef, a - b)
[docs]def varmul(a, b, undef=-9999.):
"""
Multiplication:
x = varmul(a, b) means x = a * b, where a and b are ndarray or float.
Parameters
----------
a : ndarray
input variable 1
b : ndarray
input variable 2
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
Multiplication
History
-------
Written, Matthias Cuntz, Jun 2014
"""
return np.where((a==undef) | (b==undef), undef, a * b)
[docs]def vardiv(a, b, undef=-9999.):
"""
Division:
x = vardiv(a, b) means x = a/b, where a and b are ndarray or float.
Parameters
----------
a : ndarray
dividend
b : ndarray
divisor
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
Division
History
-------
Written, Matthias Cuntz, Jun 2014
"""
return np.where((a==undef) | (b==undef), undef, _div(a, b, undef))
[docs]def varsqr(a, undef=-9999.):
"""
Square root:
x = varsqr(a) means x = sqrt(a), where a is ndarray or float.
Parameters
----------
a : ndarray
input variable
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
Square root
History
-------
Written, Matthias Cuntz, Jun 2014
"""
return np.where((a==undef), undef, np.sqrt(a))
[docs]def varsqrt(a, undef=-9999.):
"""
Square root:
x = varsqrt(a) means x = sqrt(a), where a is ndarray or float.
Parameters
----------
a : ndarray
input variable
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
Square root
History
-------
Written, Matthias Cuntz, Jun 2014
"""
return np.where((a==undef), undef, np.sqrt(a))
[docs]def varexp(a, undef=-9999.):
"""
Exponentiation of e:
x = varexp(a) means x = exp(a), where a is ndarray or float.
Parameters
----------
a : ndarray
exponent
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
Exponentiation
History
-------
Written, Matthias Cuntz, Jun 2014
"""
return np.where((a==undef), undef, np.exp(a))
[docs]def varlog(a, undef=-9999.):
"""
Natural logarithm:
x = varlog(a) means x = ln(a), where a is ndarray or float.
Parameters
----------
a : ndarray
input variable
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
Natural logarithm
History
-------
Written, Matthias Cuntz, Jun 2014
"""
return np.where((a==undef), undef, np.log(a))
[docs]def varpot(a, b, undef=-9999.):
"""
Exponentiation:
x = varpot(a, b) means x = a**b, where a and b are ndarray or float.
Parameters
----------
a : ndarray
base
b : ndarray
exponent
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
Exponentiation
History
-------
Written, Matthias Cuntz, Jun 2014
"""
return np.where((a==undef) | (b==undef), undef, a**b)
[docs]def lin(y, a0, a1, undef=-9999.):
"""
Apply linear function:
x = lin(y, a0, a1) means x = a0 + a1 * y
Parameters
----------
y : ndarray
input variable
a0 : ndarray or float
parameter 1
a1 : ndarray or float
parameter 2
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
linear function
History
-------
Written, Matthias Cuntz, Jun 2014
"""
return np.where((y==undef), undef, a0 + a1*y)
[docs]def quad(y, a0, a1, a2, undef=-9999.):
"""
Apply 2nd order function:
x=quad(y,a0,a1,a2) means x = a0 + a1*y + a2*y**2
Parameters
----------
y : ndarray
input variable
a0 : ndarray or float
parameter 1
a1 : ndarray or float
parameter 1
a2 : ndarray or float
parameter 1
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
2nd order function
History
-------
Written, Matthias Cuntz, Jun 2014
"""
return np.where((y==undef), undef, a0 + a1*y + a2*y*y)
[docs]def cubic(y, a0, a1, a2, a3, undef=-9999.):
"""
Apply 3rd order function:
x=cubic(y,a0,a1,a2,a3) means x = a0 + a1*y + a2*y**2 + a3*y**3
Parameters
----------
y : ndarray
input variable
a0 : ndarray or float
parameter 1
a1 : ndarray or float
parameter 2
a2 : ndarray or float
parameter 3
a3 : ndarray or float
parameter 4
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
3rd order function
History
-------
Written, Matthias Cuntz, Jun 2014
"""
return np.where((y==undef), undef, a0 + a1*y + a2*y*y + a3*y*y*y)
[docs]def hms(h, m, s, undef=-9999.):
"""
Calculate fraction of day from hours, minutes and seconds:
x = hms(h, m, s) means x = (h + m/60 + s/3600)/24
Parameters
----------
h : ndarray
hour
m : ndarray
minute
s : ndarray
second
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
fraction of day
History
-------
Written, Matthias Cuntz, Jun 2014
"""
return np.where((h==undef) | (m==undef) | (s==undef), undef, (h+m/60.+s/3600.)/24.)
[docs]def bit_test(y, b, start=0):
"""
Bitwise test:
x = bit_test(y, b, start=0) means x = 1 if bit b is set in y otherwise x = 0.
Returns a list if b is an array.
Counting of b starts at start.
For the behaviour of the original logger tools, set start=1.
Negative b's is not implemented.
Parameters
----------
y : ndarray
input variable 1
b : int or ndarray
input variable 2
start : int, optional
Counting of `b` starts at start (default: 0)
Returns
-------
int or list
Bitwise test
History
-------
Written, Matthias Cuntz, Jun 2014
"""
if np.size(b) > 1:
return [ (y >> i+start)%2 for i in b ]
else:
return (y >> b+start)%2
[docs]def setlow(y, low, islow=None, undef=-9999.):
"""
Replacement of underflows by new value:
x = setlow(y,low,islow) means IF (y < low) THEN x = islow ELSE x = y
islow is optional. If not given low will be used.
This function may be used to adjust small negative values of short wave radiation
during nighttime to zero values.
Parameters
----------
y : ndarray
input variable
low : ndarray
lower threshold
islow : None or ndarray, optional
if not None, use islow in case of y < low
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
underflows replaced by new value
History
-------
Written, Matthias Cuntz, Jun 2014
"""
if islow is None:
out = np.maximum(y, low)
else:
out = np.where(y < low, islow, y)
return np.where(y == undef, undef, out)
[docs]def sethigh(y, high, ishigh=None, undef=-9999.):
"""
Replacement of overflows by new value:
x = sethigh(y,high,ishigh) means IF (y > high) THEN x = ishigh ELSE x = y
ishigh is optional. If not given high will be used.
This function may be used to adjust relative humidity values of a little bit more than 100 % to 100 %.
Parameters
----------
y : ndarray
input variable
high : ndarray
upper threshold
ishigh : None or ndarray, optional
if not None, use ishigh in case of y > high
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
overflows replaced by new value
History
-------
Written, Matthias Cuntz, Jun 2014
"""
if ishigh is None:
out = np.minimum(y, high)
else:
out = np.where(y > high, ishigh, y)
return np.where(y == undef, undef, out)
[docs]def limits(y, mini, maxi, undef=-9999.):
"""
Replacement of underflows or overflows by undef:
x = limits(y, mini, maxi) means IF (y < mini) OR (y > maxi) THEN x = undef ELSE x = y
This function may be used to check values lying in between certain limits.
If one of the limits is exceeded the value is set to undef.
Parameters
----------
y : ndarray
input variable
mini : ndarray
lower threshold
maxi : ndarray
upper threshold
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
underflows or overflows replaced by `undef`
History
-------
Written, Matthias Cuntz, Jun 2014
"""
return np.where((y >= mini) & (y <= maxi), y, undef)
[docs]def mean(y, axis=None, undef=-9999.):
"""
Calculation of mean value:
x = mean(y) means x = (y[0] + y[1] + ... + y[n-1])/n
Parameters
----------
y : ndarray
input variable
axis : None or int or tuple of ints, optional
Axis or axes along which the means are computed.
The default is to compute the mean of the flattened array.
If this is a tuple of ints, a mean is performed over multiple axes,
instead of a single axis or all the axes as before.
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
mean value
History
-------
Written, Matthias Cuntz, Jun 2014
"""
return np.ma.mean(np.ma.array(y, mask=(y==undef)), axis=axis).filled(undef)
[docs]def mini(y, axis=None, undef=-9999.):
"""
Calculation of minimum value:
x = mini(y) means x = min(y[0],y[1],...,y[n-1])
Parameters
----------
y : ndarray
input variable
axis : None or int or tuple of ints, optional
Axis or axes along which the minimum are computed.
The default is to compute the minimum of the flattened array.
If this is a tuple of ints, a minimum is performed over multiple axes,
instead of a single axis or all the axes as before.
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
minimum value
History
-------
Written, Matthias Cuntz, Jun 2014
"""
return np.ma.amin(np.ma.array(y, mask=(y==undef)), axis=axis).filled(undef)
[docs]def maxi(y, axis=None, undef=-9999.):
"""
Calculation of maximum value:
x = maxi(y) means x = max(y[0],y[1],...,y[n-1])
Parameters
----------
y : ndarray
input variable
axis : None or int or tuple of ints, optional
Axis or axes along which the maximum are computed.
The default is to compute the maximum of the flattened array.
If this is a tuple of ints, a maximum is performed over multiple axes,
instead of a single axis or all the axes as before.
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
maximum value
History
-------
Written, Matthias Cuntz, Jun 2014
"""
return np.ma.amax(np.ma.array(y, mask=(y==undef)), axis=axis).filled(undef)
# Not implemented: met_torad
[docs]def met_lwrad(y, Tp, undef=-9999.): # assumes that y was already multiplied with calibration factor
"""
Calculation of long wave radiation from net radiometer:
x = met_lwrad(y, Tp)
The total radiation in W m-2 is calculated according to the following formula:
x = y*fl + sigma*(Tp+T0)**4
where sigma = 5.67051 * 10**8 W m-2 K-4 is the Stephan-Boltzmann-Constant and
fl is the factor for long wave radiation (reciprocal value of sensitivity) in W m-2 per mV.
The function assumes that fl was already applied before.
Parameters
----------
y : ndarray
output voltage of the net radiometer [mV]
Tp : ndarray
pyranometer temperature, i.e. the temperature of the net radiometer body [degC]
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
total radiation in W m-2
History
-------
Written, Matthias Cuntz, Jun 2014
"""
return np.where((y==undef) | (Tp==undef), undef, y + sigma * (Tp+T0)**4)
[docs]def met_trad(Rl, epsilon, undef=-9999.):
"""
Calculation of radiation temperature from long wave radiation:
x = met_trad(Rl, epsilon)
The radiation temperature in degC is calculated according to the following formula:
x= sqrt4(Rl/(sigma*epsilon)) - T0
where sigma = 5.67051 * 108 W m-2 K-4 is the Stephan-Boltzmann-Constant.
Parameters
----------
Rl : ndarray
longwave radiation [W m-2]
epsilon : ndarray
long wave emissivity of the surface [0-1]
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
radiation temperature in degC
History
-------
Written, Matthias Cuntz, Jun 2014
"""
const = 1./(epsilon*sigma)
trad = np.ma.sqrt(np.ma.sqrt(const*np.ma.array(Rl, mask=(Rl==undef)))) - T0
return trad.filled(undef)
[docs]def met_alb(swd, swu, swdmin=50., swumin=10., undef=-9999.):
"""
Calculation of albedo from short wave downward and upward radiation:
x = met_alb(swd, swu)
The albedo in % is calculated according to the following formula:
x = 100 * ( swu / swd )
If swd < swdmin (50 W m-2) or swu < swumin (10 W m-2) the result is undef.
Parameters
----------
swd : ndarray
shortwave downward radiation [W m-2]
swu : ndarray
shortwave upward radiation [W m-2]
swdmin : float, optional
If `swd` < `swdmin` the result is undef (default: 50).
swumin : float, optional
If `swu` < `swumin` the result is undef (default: 10).
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
albedo in %
History
-------
Written, Matthias Cuntz, Jun 2014
"""
return np.where((swd==undef) | (swu==undef) | (swd<swdmin) | (swu<swumin),
undef, _div(swu*100., swd, undef))
[docs]def met_albl(swd, swu, swdmin, swumin, undef=-9999.):
"""
Calculation of albedo from short wave downward and upward radiation with limits:
x=met_albl(swd,swu,swdmin,swumin)
The albedo in % is calculated according to the following formula:
x = 100 * ( swu / swd )
If swd < swdmin or swu < swumin the result is `undef`.
Parameters
----------
swd : ndarray
shortwave downward radiation [W m-2]
swu : ndarray
shortwave upward radiation [W m-2]
swdmin : float
If `swd` < `swdmin` the result is undef.
swumin : float
If `swu` < `swumin` the result is undef.
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
albedo in %
History
-------
Written, Matthias Cuntz, Jun 2014
"""
return np.where((swd==undef) | (swu==undef) | (swd<swdmin) | (swu<swumin),
undef, _div(swu*100., swd, undef))
[docs]def met_vpmax(temp, undef=-9999.):
"""
Calculation of saturation water vapour pressure:
x = met_vpmax(T) where
The saturation water vapour pressure in mbar (hPa) is calculated according to the following formula:
x = 6.1078 * exp(17.08085 * T / (234.175 + T))
Parameters
----------
temp : ndarray
air temperature [degC]
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
saturation water vapour pressure in mbar (hPa)
History
-------
Written, Matthias Cuntz, Jun 2014
"""
es = _esat(np.ma.array(temp+T0, mask=(temp==undef)))*0.01
return es.filled(undef)
[docs]def met_vpact(temp, rh, undef=-9999.):
"""
Calculation of actual water vapour pressure:
x = met_vpact(T,rh)
The actual water vapour pressure in mbar (hPa) is calculated according to the following formulas:
Es = 6.1078*exp(17.08085*T/ (234.175 + T))
x = Es * rh/100
Parameters
----------
temp : ndarray
air temperature [degC]
rh : ndarray
relative humidity [%]
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
actual water vapour pressure in mbar (hPa)
History
-------
Written, Matthias Cuntz, Jun 2014
"""
es = _esat(np.ma.array(temp+T0, mask=((temp==undef)|(rh==undef))))*0.01
ea = es*rh*0.01
return ea.filled(undef)
[docs]def met_vpdef(temp, rh, undef=-9999.):
"""
Calculation of water vapour pressure deficit:
x = met_vpdef(T, rh)
The water vapour pressure deficit in mbar (hPa) is calculated according to the following formulas:
Es = 6.1078*exp(17.08085*T/ (234.175 + T))
E = Es * rh/100
x = Es - E
Parameters
----------
temp : ndarray
air temperature [degC]
rh : ndarray
relative humidity [%]
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
water vapour pressure deficit in mbar (hPa)
History
-------
Written, Matthias Cuntz, Jun 2014
"""
es = _esat(np.ma.array(temp+T0, mask=((temp==undef)|(rh==undef))))*0.01
ea = es*rh*0.01
vpd = es - ea
return vpd.filled(undef)
[docs]def met_sh(temp, rh, p, undef=-9999.):
"""
Calculation of specific humidity:
x = met_sh(T, rh, p)
The specific humidity in g kg-1 is calculated according to the following formulas:
Es = 6.1078*exp(17.08085*T/ (234.175 + T))
E = Es * rh/100
x = 622 * E/(p-0.378*E)
Parameters
----------
temp : ndarray
air temperature [degC]
rh : ndarray
relative humidity [%]
p : ndarray
air pressure [hPa = mbar]
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
specific humidity in g kg-1
History
-------
Written, Matthias Cuntz, Jun 2014
"""
es = _esat(np.ma.array(temp+T0, mask=((temp==undef)|(rh==undef)|(p==undef))))*0.01
ea = es*rh*0.01
sh = _div(622.*ea, (p-0.378*ea), undef)
return sh.filled(undef)
[docs]def met_tpot(temp, p, undef=-9999.):
"""
Calculation of potential temperature:
x = met_tpot(T, p)
The potential temperature in K is calculated according to the following formula:
x = (T + T0) * (1000/p)**0.286
Parameters
----------
temp : ndarray
air temperature [degC]
p : ndarray
air pressure [hPa = mbar]
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
potential temperature in K
History
-------
Written, Matthias Cuntz, Jun 2014
"""
return np.where((temp==undef) | (p==undef), undef, (temp+T0)*_div(1000.,p)**0.286)
[docs]def met_rho(temp, rh, p, undef=-9999.):
"""
Calculation of air density:
x = met_rho(T, rh, p)
The air density in kg m-3 is calculated according to the following formulas:
Es = 6.1078*exp(17.08085*T/ (234.175 + T))
E = Es * rh/100
sh = 622 * E/(p-0.378*E)
Tv = ((T + T0) * (1 + 0.000608 * sh)) - T0
x = p * 100 / (287.05 * (Tv + T0))
Parameters
----------
temp : ndarray
air temperature [degC]
rh : ndarray
relative humidity [%]
p : ndarray
air pressure [hPa = mbar]
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
air density in kg m-3
History
-------
Written, Matthias Cuntz, Jun 2014
"""
es = _esat(np.ma.array(temp+T0, mask=((temp==undef)|(rh==undef)|(p==undef))))*0.01
ea = es*rh*0.01
sh = _div(622.*ea, (p-0.378*ea), undef)
Tv = ((temp+T0)*(1+0.000608*sh)) - T0
rho = _div(p*100., (287.05*(Tv+T0)), undef)
return rho.filled(undef)
[docs]def met_dpt(temp, rh, undef=-9999.):
"""
Calculation of dew point temperature:
x = met_dpt(T, rh)
The dew point temperature in degC is calculated according to the following formulas:
Es = 6.1078*exp(17.08085*T/(234.175 + T))
E = Es * rh/100
x = 234.175 * ln(E/6.1078)/(17.08085 - ln(E/6.1078))
Parameters
----------
temp : ndarray
air temperature [degC]
rh : ndarray
relative humidity [%]
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
dew point temperature in degC
History
-------
Written, Matthias Cuntz, Jun 2014
"""
es = _esat(np.ma.array(temp+T0, mask=((temp==undef)|(rh==undef))))*0.01
ea = es*rh*0.01
dpt = 234.175 * np.ma.log(ea/6.1078) / (17.08085 - np.ma.log(ea/6.1078))
return dpt.filled(undef)
[docs]def met_h2oc(temp, rh, p, undef=-9999.):
"""
Calculation of water vapour concentration:
x = met_h2oc(T, rh, p)
The water vapour concentration in mmol mol-1 is calculated according to the following formulas:
Es = 6.1078*exp(17.08085*T/ (234.175 + T))
E = Es * rh/100
x = 0.1 * E /(0.001*p*100*0.001)
Parameters
----------
temp : ndarray
air temperature [degC]
rh : ndarray
relative humidity [%]
p : ndarray
air pressure [hPa = mbar]
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
water vapour concentration in mmol mol-1
History
-------
Written, Matthias Cuntz, Jun 2014
"""
es = _esat(np.ma.array(temp+T0, mask=((temp==undef)|(rh==undef)|(p==undef))))*0.01
ea = es*rh*0.01
c = _div(1000.*ea, p, undef)
return c.filled(undef)
# Not implemented: met_psy_rh
# Not implemented: met_dpt_rh
[docs]def met_h2oc_rh(temp, h, p, undef=-9999.):
"""
Calculation of relative humidity from water vapour concentration:
x = met_h2oc_rh(T, [H2O], p)
The relative humidity in % is calculated according to the following formulas:
Es = 6.1078*exp(17.08085*T/(234.175 + T))
E = 10 * [H2O] * 0.001 * p * 100 * 0.001
x = 100 * E / Es
Parameters
----------
temp : ndarray
air temperature [degC]
h : ndarray
water vapour concentration [mmol mol-1]
p : ndarray
air pressure [hPa = mbar]
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
relative humidity in %
History
-------
Written, Matthias Cuntz, Jun 2014
"""
es = _esat(np.ma.array(temp+T0, mask=((temp==undef)|(h==undef)|(p==undef))))*0.01
ea = 0.001 * h * p
c = 100.*ea/es
return c.filled(undef)
[docs]def met_wdrot(wd, a, undef=-9999.):
"""
Rotation of wind direction:
x = met_wdrot(wd, a)
The rotated wind direction is calculated according to the following formulas:
x = wd + a
IF x < 0 THEN x = x + 360
IF x <= 360 THEN x = x - 360
Parameters
----------
wd : ndarray
wind direction [degree]
a : ndarray
rotation angle (positive is clockwise) [degree]
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
rotated wind direction
History
-------
Written, Matthias Cuntz, Jun 2014
"""
rot = np.ma.array(wd+a, mask=((wd==undef)|(a==undef)))
rot = np.ma.where(rot < 0., rot+360., rot)
rot = np.ma.where(rot >= 360., rot-360., rot)
return rot.filled(undef)
[docs]def met_urot(u, v, a, undef=-9999.):
"""
Rotation of u-component of wind vector:
x = met_urot(u, v, a)
The rotated u-component is calculated according to the following formula:
x = u * cos (a) + v * sin (a)
Parameters
----------
u : ndarray
u-component of the wind vector
v : ndarray
v-component of the wind vector
a : ndarray
rotation angle (positive is clockwise) [degree]
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
rotated u-component
History
-------
Written, Matthias Cuntz, Jun 2014
"""
return np.where((u==undef) | (v==undef) | (a==undef), undef, u*np.cos(np.deg2rad(a)) + v*np.sin(np.deg2rad(a)))
[docs]def met_vrot(u, v, a, undef=-9999.):
"""
Rotation of v-component of wind vector:
x = met_vrot(u, v, a)
The rotated v-component is calculated according to the following formula:
x = -u * sin (a) + v * cos (a)
Parameters
----------
u : ndarray
u-component of the wind vector
v : ndarray
v-component of the wind vector
a : ndarray
rotation angle (positive is clockwise) [degree]
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
rotated v-component
History
-------
Written, Matthias Cuntz, Jun 2014
"""
return np.where((u==undef) | (v==undef) | (a==undef), undef, -u*np.sin(np.deg2rad(a)) + v*np.cos(np.deg2rad(a)))
[docs]def met_uv_wv(u, v, undef=-9999.):
"""
Calculation of wind velocity from u- and v-component of wind vector:
x = met_uv_wv(u, v)
The horizontal wind velocity is calculated according to the following formula:
x = sqrt(u**2 + v**2)
Parameters
----------
u : ndarray
u-component of the wind vector
v : ndarray
v-component of the wind vector
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
horizontal wind velocity
History
-------
Written, Matthias Cuntz, Jun 2014
"""
return np.where((u==undef) | (v==undef), undef, np.sqrt(u*u + v*v))
[docs]def met_uv_wd(u, v, undef=-9999.):
"""
Calculation of wind direction from u- and v-component of wind vector:
x = met_uv_wd(u, v)
The horizontal wind velocity is calculated according to the following formulas:
IF u = 0 AND v = 0 THEN x = 0
IF u = 0 AND v < 0 THEN x = 360
IF u = 0 AND v > 0 THEN x = 180
IF u > 0 THEN x = 270 - arctan(v/u)
IF u < 0 THEN x = 90 - arctan(v/u)
Parameters
----------
u : ndarray
u-component of the wind vector
v : ndarray
v-component of the wind vector
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
horizontal wind velocity
History
-------
Written, Matthias Cuntz, Jun 2014
"""
wd = np.ma.zeros(u.shape)
wd.mask = (u==undef) | (v==undef)
wd = np.ma.where((u==0.) & (v==0.), 0., wd)
wd = np.ma.where((u==0.) & (v<0.), 360., wd)
wd = np.ma.where((u==0.) & (v>0.), 180., wd)
wd = np.ma.where((u>0.), 270.-np.rad2deg(np.ma.arctan(v/u)), wd)
wd = np.ma.where((u<0.), 90.-np.rad2deg(np.ma.arctan(v/u)), wd)
return wd.filled(undef)
[docs]def met_wvwd_u(wv, wd, undef=-9999.):
"""
Calculation of u-component of wind vector from wind velocity and wind direction:
x = met_wvwd_u(wv, wd)
The u-component of the wind vector is calculated according to the following formula:
x = -wv * sin (wd)
Parameters
----------
wv : ndarray
horizontal wind velocity [m s-1]
wd : ndarray
horizontal wind direction [degree]
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
u-component of the wind vector
History
-------
Written, Matthias Cuntz, Jun 2014
"""
return np.where((wv==undef) | (wd==undef), undef, -wv*np.sin(np.deg2rad(wd)))
[docs]def met_wvwd_v(wv, wd, undef=-9999.):
"""
Calculation of v-component of wind vector from wind velocity and wind direction:
x = met_wvwd_v(wv, wd)
The v-component of the wind vector is calculated according to the following formula:
x = -wv * cos (wd)
Parameters
----------
wv : ndarray
horizontal wind velocity [m s-1]
wd : ndarray
horizontal wind direction [degree]
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
v-component of the wind vector
History
-------
Written, Matthias Cuntz, Jun 2014
"""
return np.where((wv==undef) | (wd==undef), undef, -wv*np.cos(np.deg2rad(wd)))
[docs]def ifeq(y, a0, a1, a2):
"""
If-statements:
x = ifeq(y,a0,a1,a2) means IF y == a0 THEN x = a1 ELSE x = a2
Parameters
----------
y : ndarray
input variable
a0 : ndarray
compare to input `y == a0`
a1 : ndarray
result if `y == a0`
a2 : ndarray
result if `y != a0`
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
IF y == a0 THEN x = a1 ELSE x = a2
History
-------
Written, Matthias Cuntz, Jun 2014
"""
out = np.where(y == a0, a1, a2)
return np.where((y==undef) | (a0==undef) | (a1==undef) | (a2==undef), undef, out)
[docs]def ifne(y, a0, a1, a2):
"""
If-statements:
x = ifne(y,a0,a1,a2) means IF y != a0 THEN x = a1 ELSE x = a2
Parameters
----------
y : ndarray
input variable
a0 : ndarray
compare to input `y != a0`
a1 : ndarray
result if `y != a0`
a2 : ndarray
result if `y == a0`
y : ndarray
a0 : ndarray
a1 : ndarray
a2 : ndarray
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
IF y != a0 THEN x = a1 ELSE x = a2
History
-------
Written, Matthias Cuntz, Jun 2014
"""
out = np.where(y != a0, a1, a2)
return np.where((y==undef) | (a0==undef) | (a1==undef) | (a2==undef), undef, out)
[docs]def ifle(y, a0, a1, a2):
"""
If-statements:
x = ifle(y,a0,a1,a2) means IF y >= a0 THEN x = a1 ELSE x = a2
Parameters
----------
y : ndarray
input variable
a0 : ndarray
compare to input `y <= a0`
a1 : ndarray
result if `y <= a0`
a2 : ndarray
result if `y > a0`
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
IF y >= a0 THEN x = a1 ELSE x = a2
History
-------
Written, Matthias Cuntz, Jun 2014
"""
out = np.where(y <= a0, a1, a2)
return np.where((y==undef) | (a0==undef) | (a1==undef) | (a2==undef), undef, out)
[docs]def ifge(y, a0, a1, a2):
"""
If-statements:
x = ifge(y,a0,a1,a2) means IF y <= a0 THEN x = a1 ELSE x = a2
Parameters
----------
y : ndarray
input variable
a0 : ndarray
compare to input `y >= a0`
a1 : ndarray
result if `y >= a0`
a2 : ndarray
result if `y < a0`
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
IF y <= a0 THEN x = a1 ELSE x = a2
History
-------
Written, Matthias Cuntz, Jun 2014
"""
out = np.where(y <= a0, a1, a2)
return np.where((y==undef) | (a0==undef) | (a1==undef) | (a2==undef), undef, out)
[docs]def iflt(y, a0, a1, a2):
"""
If-statements:
x = iflt(y,a0,a1,a2) means IF y < a0 THEN x = a1 ELSE x = a2
Parameters
----------
y : ndarray
input variable
a0 : ndarray
compare to input `y < a0`
a1 : ndarray
result if `y < a0`
a2 : ndarray
result if `y >= a0`
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
IF y < a0 THEN x = a1 ELSE x = a2
History
-------
Written, Matthias Cuntz, Jun 2014
"""
out = np.where(y < a0, a1, a2)
return np.where((y==undef) | (a0==undef) | (a1==undef) | (a2==undef), undef, out)
[docs]def ifgt(y, a0, a1, a2):
"""
If-statements:
x = ifgt(y,a0,a1,a2) means IF y > a0 THEN x = a1 ELSE x = a2
Parameters
----------
y : ndarray
input variable
a0 : ndarray
compare to input `y > a0`
a1 : ndarray
result if `y > a0`
a2 : ndarray
result if `y <= a0`
undef : float, optional
elements are excluded from the calculations if any of the inputs equals `undef` (default: -9999.)
Returns
-------
ndarray
IF y > a0 THEN x = a1 ELSE x = a2
History
-------
Written, Matthias Cuntz, Jun 2014
"""
out = np.where(y > a0, a1, a2)
return np.where((y==undef) | (a0==undef) | (a1==undef) | (a2==undef), undef, out)
# Not implemented: write
#
# Local replacement functions if helper functions do not exist in library
#
def _div(a, b, otherwise=np.nan, prec=0.):
"""
Divide two arrays, return `otherwise` if division by 0.
Copy of ..division.py
Parameters
----------
a : array_like
enumerator
b : array_like
denominator
otherwise : float
value to return if `b=0` (default: `np.nan`)
prec : float
if |b|<|prec| then `otherwise`
Returns
-------
ndarray
ratio : numpy array or masked array
a/b if |b| > |prec|
otherwise if |b| <= |prec|
Output is numpy array. It is a masked array if at least one
of `a` or `b` is a masked array.
"""
oldsettings = np.geterr()
np.seterr(divide='ignore')
if isinstance(a, np.ma.masked_array) or isinstance(b, np.ma.masked_array):
out = np.ma.where(np.ma.abs(np.ma.array(b)) > np.abs(prec), np.ma.array(a)/np.ma.array(b), otherwise)
else:
out = np.where(np.abs(np.array(b)) > np.abs(prec), np.array(a)/np.array(b), otherwise)
np.seterr(**oldsettings)
return out
def _esat(T):
"""
Calculates the saturation vapour pressure of water with the Goff-Gratch formula.
From ..esat.py
Parameters
----------
T : ndarray
Temperature [K]
Returns
-------
ndarray
Saturation water pressure at temperature T in Pascal [Pa].
"""
Ts = 373.16 # steam point temperature in K
ews = 1013.246 # saturation pressure at steam point temperature, normal atmosphere
esat_liq = 10.**(-7.90298*(Ts/T-1.) + 5.02808 * np.ma.log10(Ts/T)
- 1.3816e-7 * (10.**(11.344*(1.-T/Ts))-1.)
+ 8.1328e-3 * (10.**(-3.49149*(Ts/T-1.))-1.) + np.ma.log10(ews)) # [hPa]
return esat_liq * 100. # [Pa]
if __name__ == '__main__':
import doctest
doctest.testmod(optionflags=doctest.NORMALIZE_WHITESPACE)