Validation results ITU-R P.676-12

This page contains the validation examples for Recommendation ITU-R P.676-12: Attenuation by atmospheric gases and related effects.

All test cases were extracted from the ITU Validation examples file (rev 5.1).

Functions tested

Function gaseous_attenuation_slant_path

The table below contains the results of testing function gaseous_attenuation_slant_path. The test cases were extracted from spreadsheet ITURP676-12_A_gas.csv from the ITU Validation examples file (rev 5.1). In addition to the input-arguments, expected result (ITU Validation), and ITU-Rpy computed result (ITUR-py Result), the absolute and relative errors are shown. Each test case is color-coded depending on the magnitude of the errors (green = pass, errors are negligible, red = fail, relative error is above 0.01%).

In addition, the code snippet below shows an example of how to generate the first row of the results in the table:

import itur

# Define input attributes
f = 14.25  # (GHz)
el = 31.07699124  # (°)
rho = 13.79653679  # (g/m3)
P = 1009.485612  # (hPA)
T = 283.6108756  #  (C)
h = 0.031382984  # (km)
V_t = 33.72946527  #  (kg/m2)

# Make call to test-function gaseous_attenuation_slant_path
itur_val = itur.models.itu676.gaseous_attenuation_slant_path(f=f, el=el, rho=rho, P=P, T=T, h=h, V_t=V_t)

# Compute error with respect to value in ITU example file
ITU_example_val = 0.226874038  # (dB)
error = ITU_example_val - itur_val.value
error_rel = error / ITU_example_val * 100  # (%)

Function gamma_exact

The table below contains the results of testing function gamma_exact. The test cases were extracted from spreadsheet ITURP676-12_gamma.csv from the ITU Validation examples file (rev 5.1). In addition to the input-arguments, expected result (ITU Validation), and ITU-Rpy computed result (ITUR-py Result), the absolute and relative errors are shown. Each test case is color-coded depending on the magnitude of the errors (green = pass, errors are negligible, red = fail, relative error is above 0.01%).

In addition, the code snippet below shows an example of how to generate the first row of the results in the table:

import itur

# Define input attributes
f = 12.0  # (GHz)
P = 1013.25  # (hPA)
rho = 7.5  # (g/cm3)
T = 288.15  # (K)

# Make call to test-function gamma_exact
itur_val = itur.models.itu676.gamma_exact(f=f, P=P, rho=rho, T=T)

# Compute error with respect to value in ITU example file
ITU_example_val = 0.018233652  # (dB/km)
error = ITU_example_val - itur_val.value
error_rel = error / ITU_example_val * 100  # (%)

Function gamma0_exact

The table below contains the results of testing function gamma0_exact. The test cases were extracted from spreadsheet ITURP676-12_gamma.csv from the ITU Validation examples file (rev 5.1). In addition to the input-arguments, expected result (ITU Validation), and ITU-Rpy computed result (ITUR-py Result), the absolute and relative errors are shown. Each test case is color-coded depending on the magnitude of the errors (green = pass, errors are negligible, red = fail, relative error is above 0.01%).

In addition, the code snippet below shows an example of how to generate the first row of the results in the table:

import itur

# Define input attributes
f = 12.0  # (GHz)
P = 1013.25  # (hPA)
rho = 7.5  # (g/cm3)
T = 288.15  # (K)

# Make call to test-function gamma0_exact
itur_val = itur.models.itu676.gamma0_exact(f=f, P=P, rho=rho, T=T)

# Compute error with respect to value in ITU example file
ITU_example_val = 0.008698264  # (dB/km)
error = ITU_example_val - itur_val.value
error_rel = error / ITU_example_val * 100  # (%)

Function gammaw_exact

The table below contains the results of testing function gammaw_exact. The test cases were extracted from spreadsheet ITURP676-12_gamma.csv from the ITU Validation examples file (rev 5.1). In addition to the input-arguments, expected result (ITU Validation), and ITU-Rpy computed result (ITUR-py Result), the absolute and relative errors are shown. Each test case is color-coded depending on the magnitude of the errors (green = pass, errors are negligible, red = fail, relative error is above 0.01%).

In addition, the code snippet below shows an example of how to generate the first row of the results in the table:

import itur

# Define input attributes
f = 12.0  # (GHz)
P = 1013.25  # (hPA)
rho = 7.5  # (g/cm3)
T = 288.15  # (K)

# Make call to test-function gammaw_exact
itur_val = itur.models.itu676.gammaw_exact(f=f, P=P, rho=rho, T=T)

# Compute error with respect to value in ITU example file
ITU_example_val = 0.009535388  # (dB/km)
error = ITU_example_val - itur_val.value
error_rel = error / ITU_example_val * 100  # (%)

Function zenit_water_vapour_attenuation

The table below contains the results of testing function zenit_water_vapour_attenuation. The test cases were extracted from spreadsheet ITURP676-12_zenith_attenuation.csv from the ITU Validation examples file (rev 5.1). In addition to the input-arguments, expected result (ITU Validation), and ITU-Rpy computed result (ITUR-py Result), the absolute and relative errors are shown. Each test case is color-coded depending on the magnitude of the errors (green = pass, errors are negligible, red = fail, relative error is above 0.01%).

In addition, the code snippet below shows an example of how to generate the first row of the results in the table:

import itur

# Define input attributes
lat = 0.0  #  (°N)
lon = 0.0  # (°E)
p = 0.0  # (hPa)
f = 14.25  # (GHz)
h = 0.031382984  # (km)
V_t = 33.72946527  #  (kg/m2)

# Make call to test-function zenit_water_vapour_attenuation
itur_val = itur.models.itu676.zenit_water_vapour_attenuation(lat=lat, lon=lon, p=p, f=f, h=h, V_t=V_t)

# Compute error with respect to value in ITU example file
ITU_example_val = 0.070935174  # (dB/km)
error = ITU_example_val - itur_val.value
error_rel = error / ITU_example_val * 100  # (%)