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measures.earthmagnetic - Function

1.4.1 define an earthmagnetic measure


Description

earthmagnetic defines an earthmagnetic measure from the CLI. It needs a reference code, earthmagnetic quantity values (see introduction for the action on a scalar quantity with either a vector or scalar value) if the reference code is not for a model, and optionally it can specify an offset, which in itself has to be a earthmagnetic. In general you specify a model (IGRF is the default and the only one known) and convert it to an explicit field. (See

http://fdd.gsfc.nasa.gov/IGRF.html

for information on the International Geomagnetic Reference Field). The earthmagnetic quantity values should be either longitude (angle), latitude(angle) and length(field strength); or x,y,z (field). See quantity for possible angle formats.

Arguments

Inputs

rf

reference code

allowed:

string

Default:

IGRF

v0

Field strength

allowed:

any

Default:

variant

v1

longitude

allowed:

any

Default:

variant

v2

latitude

allowed:

any

Default:

variant

off

optional offset earthmagnetic measure

allowed:

record

Default:

Returns
record

Example

 
 
print "\t----\t earthmagnetic Ex 1 \t----"  
print me.earthmagnetic(’igrf’)  
#{’type’: ’earthmagnetic’, ’refer’: ’IGRF’, ’m1’: {’value’: 0.0, ’unit’: ’nT’},  
# ’m0’: {’value’: 6.1230317691118855e-23, ’unit’: ’nT’},  
# ’m2’: {’value’: 9.9999999999999995e-07, ’unit’: ’nT’}}  
print me.doframe(me.observatory(’atca’))  
print me.doframe(me.source(’1934-638’))  
print me.doframe(me.epoch(’utc’,qa.unit(’today’)))  
print me.measure(me.earthmagnetic(’igrf’), ’j2000’)  
#{’type’: ’earthmagnetic’, ’refer’: ’J2000’,  
# ’m1’: {’value’: -8664.8767628222304, ’unit’: ’nT’},  
# ’m0’: {’value’: 50544.054410564473, ’unit’: ’nT’},  
# ’m2’: {’value’: 1799.5131920958615, ’unit’: ’nT’}}  
 

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