Boyer-Lindquist/Cartesian Coordinate Transformations

einsteinpy.utils.bl_coord_transforms.CartesianToBL_pos(pos_vec, a)

Function to convert Cartesian to Boyer-Lindquits coordinates (position vector)

Parameters

  • pos_vec (array) – 3-length numpy array having x, y, z coordinates in SI units(m)

  • a (float) – Any constant

Returns

3-length numpy array with r, theta, phi in (m, rad, rad)

Return type

array

einsteinpy.utils.bl_coord_transforms.CartesianToBL_vel(pos_vec, vel_vec, a)

Function to convert velocity in Cartesian coordinates to velocity in Boyer-Lindquist coordinates

Parameters

  • pos_vec (array) – 3-length numpy array having x, y, z coordinates in SI units(m)

  • vel_vec (array) – 3-length numpy array with vx, vy, vz in (m/s)

  • a (float) – Any constant

Returns

3-length numpy array having v_r, v_theta, v_phi in (m/s, rad/s, rad/s)

Return type

array

einsteinpy.utils.bl_coord_transforms.BLToCartesian_pos(pos_vec, a)

Function to convert Boyer-Lindquist coordinates to Cartesian coordinates

Parameters

  • pos_vec (array) – 3-length numpy array having r, theta, phi coordinates in SI units(m, rad, rad)

  • a (float) – Any constant

Returns

3-length numpy array with x, y, z in m.

Return type

array

einsteinpy.utils.bl_coord_transforms.BLToCartesian_vel(pos_vec, vel_vec, a)

Function to convert velocities in Boyer-Lindquist coordinates to velocities in Cartesian coordinates

Parameters

  • pos_vec (array) – 3-length numpy array having r, theta, phi coordinates in SI units(m, rad, rad)

  • vel_vec (array) – 3-length numpy array with V_r, V_theta, V_phi (m/s, rad/s, rad/s)

  • a (float) – Any constant

Returns

3-length numpy array having vx, vy, vz in SI units(m/s)

Return type

array

einsteinpy.utils.bl_coord_transforms.C2BL_units(pos_vec, vel_vec, a)

Function to convert Cartesian to Boyer-Lindquist Coordinates along with handling units

Parameters

  • pos_vec (list) – list of 3 position coordinates along with appropriate units [x, y, z] (u.m, u.m, u.m)

  • vel_vec (list) – list of 3 velocity coordinates along with appropriate units [vx, vy, vz] (u.m/u.s, u.m/u.s, u.m/u.s)

  • a (float) – Any constant

Returns

consisting of 2 lists ([r, theta, phi], [vr, vtheta, vphi]) in units ([u.m, u.rad, u.rad],[u.m/u.s, u.rad/u.s, u.rad/u.s])

Return type

tuple

einsteinpy.utils.bl_coord_transforms.BL2C_units(pos_vec, vel_vec, a)

Function to convert Boyer-Lindquist to Cartesian Coordinates along with handling units

Parameters

  • pos_vec (list) – list of 3 position coordinates along with appropriate units [r, theta, phi] (u.m, u.rad, u.rad)

  • vel_vec (list) – list of 3 velocity coordinates along with appropriate units [vr, vtheta, vphi] (u.m/u.s, u.rad/u.s, u.rad/u.s)

  • a (float) – Any constant

Returns

consisting of 2 lists ([x, y, z], [vx, vy, vz]) in units ([u.m, u.m, u.m],[u.m/u.s, u.m/u.s, u.m/u.s])

Return type

tuple

einsteinpy.utils.bl_coord_transforms.BL2C_8dim(vec, a)

Function to convert Boyer-Lindquist 8-length numpy array coordinates to Cartesian

Parameters

  • vec (array) – Array of shape (n,8) in the form [t,r,theta,phi,vt,vr,vtheta,vphi] in SI units.

  • a (float) – Any constant

Returns

Array of shape (n,8) in the form [t,x,y,z,vt,vx,vy,vz] in SI units

Return type

array