thermal_speed_coefficients

plasmapy.formulary.speeds.thermal_speed_coefficients(method: str, ndim: int)

Get the thermal speed coefficient corresponding to the desired thermal speed definition.

See the thermal_speed Notes section for further details of the various thermal speed definitions.

Parameters:
• method (str) – Method to be used for calculating the thermal speed. Valid values are "most_probable", "rms", "mean_magnitude", and "nrl".

• ndim (int) – Dimensionality (1D, 2D, 3D) of space in which to calculate thermal speed. Valid values are 1, 2, or 3.

Raises:

ValueError – If method or ndim are not a valid value.

Notes

For a detailed explanation of the different coefficients used to calculate the thermal speed, then look to the Notes section for thermal_speed. The possible return values are listed the following table:

 ↓ method ndim → 1 2 3 "most_probable" $0$ $1$ $\sqrt{2}$ "rms" $1$ $\sqrt{2}$ $\sqrt{3}$ "mean_magnitude" $\sqrt{2/π}$ $\sqrt{π/2}$ $\sqrt{8/π}$ "nrl" $1$

Examples

>>> thermal_speed_coefficients(method="most_probable", ndim=3)
1.414213...