flekspy.util.transformations

Functions

create_field_transform(→ Callable[[numpy.ndarray], ...)

Creates a transformation function to align velocity coordinates with E and B fields.

Module Contents

flekspy.util.transformations.create_field_transform(b_field: numpy.ndarray, original_component_names: List[str], e_field: numpy.ndarray | None = None) → Callable[[numpy.ndarray], Tuple[numpy.ndarray, List[str]]][source]

Creates a transformation function to align velocity coordinates with E and B fields.

This function returns a new transformation function that can be passed to plotter methods. The returned function takes a data array and calculates new velocity components.

  • If only b_field is provided, it calculates velocity components parallel and perpendicular to the magnetic field (v_parallel, v_perp).

  • If both b_field and e_field are provided, it creates an orthonormal basis (v_B, v_E, v_BxE) and projects the velocity onto it.

The function returns a new data array containing the original data without the old velocity components, but with the new field-aligned components appended.

Parameters:

  • b_field (np.ndarray) – The magnetic field vector (3 components).

  • original_component_names (List[str]) – The list of component names for the input data array.

  • e_field (np.ndarray, optional) – The electric field vector (3 components).

Returns:

A transformation function that takes a NumPy array and returns a tuple containing the transformed data array and the new list of component names.