chaosmagpy.chaos.load_CovObs_txtfile¶
- chaosmagpy.chaos.load_CovObs_txtfile(filepath, name=None)[source]¶
Load the ensemble mean of the internal model from the COV-OBS TXT-file in spline format.
- Parameters:
- filepathstr
Path to spline-formatted TXT-file (not part of ChaosMagPy).
- namestr, optional
User defined name of the model. Defaults to the filename without the file extension.
- Returns:
References
For details on the COV-OBS model (COV-OBS.x2), see the original publication:
Huder, L., Gillet, N., Finlay, C. C., Hammer, M. D. and H. Tchoungui (2020), “COV-OBS.x2: 180 yr of geomagnetic field evolution from ground-based and satellite observations”, Earth, Planets and Space.
Examples
Load the ensemble mean internal model and plot the degree-1 secular variation. Here, the model parameter file, e.g. “COV-OBS.x2-int”, is in the current working directory.
import chaosmagpy as cp import matplotlib.pyplot as plt import numpy as np model = cp.load_CovObs_txtfile('COV-OBS.x2-int') # load model TXT-file fig, ax = plt.subplots(1, 1, figsize=(10, 6)) # sample model timespan time = np.linspace(1840., 2020., 1000) # decimal years mjd = cp.data_utils.dyear_to_mjd(time, leap_year=False) coeffs = model.synth_coeffs(mjd, nmax=1, deriv=1) ax.plot(cp.data_utils.timestamp(time), coeffs) ax.set_title(model.name) ax.set_xlabel('Time (years)') ax.set_ylabel('nT/yr') ax.legend(['$g_1^0$', '$g_1^1$', '$h_1^1$']) plt.tight_layout() plt.show()