ChaosMagPy internally uses a number of parameters and coefficient/data files,
whose numerical values and filepaths are stored in a dictionary-like container,
basicConfig. Usually, the content of it need not be changed.
However, if for example one wishes to compute a time series of the
external field beyond the limit of the builtin RC-index file, then ChaosMagPy
can be configured to use an updates RC-index file.
To view the parameters in
basicConfig, do the following:
import chaosmagpy as cp print(cp.basicConfig)
This will print a list of the parameters than can in principle be changed.
For example, it contains Earth’s surface radius
params.r_surf, which is
used as reference radius for the spherical harmonic representation of the
magnetic potential field. For a complete list, see
Change RC index file¶
Download a new RC-index file either directly as txt-file from
or by using the function
save_RC_h5file() (saves as
from chaosmagpy.data_utils import save_RC_h5file save_RC_h5file('my_RC_file.h5')
There is no significant difference in speed when using txt-file or h5-file formats in this case. After importing ChaosMagPy, provide the path to the new RC-index file:
import chaosmagpy as cp cp.basicConfig['file.RC_index'] = './my_RC_file.h5'
This should be done at the top of the script after the import statements, otherwise ChaosMagPy uses the builtin RC-index file.
Save and load custom configuration¶
The configuration values can also be read from and written to a simple text file in json format.
For the correct format, it is best to change the configuration parameters during a python session and then save them to a file. For example, the following code sets the Earth’s surface radius to 6371 km (there is no reason to do this except for the sake of this example):
import chaosmagpy as cp cp.basicConfig['params.r_surf'] = 6371
Then save the configuration dictionary to a file:
To load this configuration file, use the following at the start of the script: