#!/usr/bin/env python
# coding: utf-8

# In[ ]:


get_ipython().run_line_magic('matplotlib', 'inline')


# 
# Braginskii coefficients
# =========================
# 
# A short example of how to calculate classical transport coefficients
# from Bragiński's theory.
# 

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from astropy import units as u

from plasmapy.formulary import ClassicalTransport


# We'll use some sample ITER data, without much regard for whether
# the regime is even fit for classical transport theory:
# 
# 

# In[ ]:


thermal_energy_per_electron = 8.8 * u.keV
electron_concentration = 10.1e19 / u.m ** 3

thermal_energy_per_ion = 8.0 * u.keV
ion_concentration = electron_concentration
ion = "D+"  # a crude approximation


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braginskii = ClassicalTransport(
    thermal_energy_per_electron,
    electron_concentration,
    thermal_energy_per_ion,
    ion_concentration,
    ion,
)


# These variables are calculated during initialization and can be
# referred to straight away:
# 
# 

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print(braginskii.coulomb_log_ei)
print(braginskii.coulomb_log_ii)
print(braginskii.hall_e)
print(braginskii.hall_i)


# These quantities are not calculated during initialization and can be
# referred to via methods. To signify the need to calculate them, we
# call them via ().
# 
# 

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print(braginskii.resistivity)
print(braginskii.thermoelectric_conductivity)
print(braginskii.electron_thermal_conductivity)
print(braginskii.ion_thermal_conductivity)


# They also change with magnetization:
# 
# 

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mag_braginskii = ClassicalTransport(
    thermal_energy_per_electron,
    electron_concentration,
    thermal_energy_per_ion,
    ion_concentration,
    ion,
    B=0.1 * u.T,
)

print(mag_braginskii.resistivity)
print(mag_braginskii.thermoelectric_conductivity)
print(mag_braginskii.electron_thermal_conductivity)
print(mag_braginskii.ion_thermal_conductivity)


# In[ ]:


all_direction_braginskii = ClassicalTransport(
    thermal_energy_per_electron,
    electron_concentration,
    thermal_energy_per_ion,
    ion_concentration,
    ion,
    B=0.1 * u.T,
    field_orientation="all",
)

print(all_direction_braginskii.resistivity)
print(all_direction_braginskii.thermoelectric_conductivity)
print(all_direction_braginskii.electron_thermal_conductivity)
print(all_direction_braginskii.ion_thermal_conductivity)


# The viscosities return arrays:
# 
# 

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print(braginskii.electron_viscosity)
print(mag_braginskii.electron_viscosity)
print(braginskii.ion_viscosity)
print(mag_braginskii.ion_viscosity)