Source code for pyrfu.pyrf.dot
#!/usr/bin/env python
# -*- coding: utf-8 -*-
# 3rd party imports
import numpy as np
# Local imports
from .resample import resample
from .ts_scalar import ts_scalar
__author__ = "Louis Richard"
__email__ = "louisr@irfu.se"
__copyright__ = "Copyright 2020-2023"
__license__ = "MIT"
__version__ = "2.4.2"
__status__ = "Prototype"
[docs]def dot(inp1, inp2):
r"""Computes dot product of two fields.
Parameters
----------
inp1 : xarray.DataArray
Time series of the first field X.
inp2 : xarray.DataArray
Time series of the second field Y.
Returns
-------
out : xarray.DataArray
Time series of the dot product Z = X.Y.
Examples
--------
>>> from pyrfu import mms, pyrf
Time interval
>>> tint = ["2019-09-14T07:54:00.000", "2019-09-14T08:11:00.000"]
Load magnetic field, electric field and spacecraft position
>>> r_mms, b_mms, e_mms = [[] * 4 for _ in range(3)]
>>> for mms_id in range(1, 5):
>>> r_mms.append(mms.get_data("R_gse", tint, mms_id))
>>> b_mms.append(mms.get_data("B_gse_fgm_srvy_l2", tint, mms_id))
>>> e_mms.append(mms.get_data("E_gse_edp_fast_l2", tint, mms_id))
Compute current density using curlometer technique
>>> j_xyz, _, _, _, _, _ = pyrf.c_4_j(r_mms, b_mms)
Compute the electric at the center of mass of the tetrahedron
>>> e_xyz = pyrf.avg_4sc(e_mms)
Compute J.E dissipation
>>> je = pyrf.dot(j_xyz, e_xyz)
"""
# Resample to first input sampling
inp2 = resample(inp2, inp1)
# Compute scalar product
out_data = np.sum(inp1.data * inp2.data, axis=1)
# Output to xarray
out = ts_scalar(inp1.time.data, out_data)
return out