Source code for foxes.utils.wind_dir

import numpy as np


[docs] def wd2wdvec(wd, ws=1.0, axis=-1): """ Calculate wind direction vectors from wind directions in degrees. Parameters ---------- wd: numpy.ndarray Wind direction array (any shape) ws: float or numpy.ndarray The wind speed. Has to broadcast against wd. axis: int Location where to insert the (x, y) dimension into the shape of wd Returns ------- wdvec: numpy.ndarray The wind direction vectors :group: utils """ wdr = wd * np.pi / 180.0 n = np.stack([np.sin(wdr), np.cos(wdr)], axis=axis) if np.isscalar(ws): return ws * n return np.expand_dims(ws, axis) * n
[docs] def wd2uv(wd, ws=1.0, axis=-1): """ Calculate wind vectors from wind directions in degrees. Parameters ---------- wd: numpy.ndarray Wind direction array (any shape) ws: float or numpy.ndarray The wind speed. Has to broadcast against wd. axis: int Axis location where to insert the (u, v) components into the shape of wd Returns ------- uv: numpy.ndarray The wind vectors :group: utils """ return -wd2wdvec(wd, ws, axis)
[docs] def uv2wd(uv, axis=-1): """ Calculate wind direction from wind vectors. Parameters ---------- uv: numpy.ndarray The wind vectors, any shape axis: int The axis which corresponds to (u, v) components Returns ------- wd: numpy.ndarray The wind direction array :group: utils """ if axis == -1: u = uv[..., 0] v = uv[..., 1] else: s = tuple(0 if a == axis else slice(None) for a in range(len(uv.shape))) u = uv[s] s = tuple(1 if a == axis else slice(None) for a in range(len(uv.shape))) v = uv[s] return np.mod(180 + np.rad2deg(np.arctan2(u, v)), 360)
[docs] def wdvec2wd(wdvec, axis=-1): """ Calculate wind direction from wind direction vectors. Parameters ---------- wdvec: numpy.ndarray The wind direction vectors, any shape axis: int The axis which corresponds to (x, y) components Returns ------- wd: numpy.ndarray The wind direction array :group: utils """ return uv2wd(-wdvec, axis)
[docs] def delta_wd(wd_a, wd_b): """ Calculates wd_b - wd_a. Parameters ---------- wd_a: numpy.ndarray Array of wind directions. Shape: any shape wd_b: numpy.ndarray Array of wind directions. Shape: same as wd_a Returns ------- numpy.ndarray : Array of wind direction deltas. Shape: same as wd_a, wd_b :group: utils """ out = wd_b - wd_a out[out < -180.0] += 360.0 out[out > 180.0] -= 360.0 return out