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measures.torestfrequency - Function

1.4.1 convert a frequency and doppler measure to a rest frequency


Description

torestfrequency will convert a frequency measure and a doppler measure (e.g. obtained from another spectral line with a known rest frequency) to a rest frequency.

Arguments





Inputs

v0

frequency reference type

allowed:

record

Default:

d0

doppler measure value

allowed:

record

Default:

Returns
record

Example

 
 
print "\t----\t torestfrequency Ex 1 \t----"  
dp = me.doppler(’radio’, ’2196.24984km/s’)  # a measured doppler speed  
print dp  
#{’m0’: {’value’: 2196249.8399999999, ’unit’: ’m/s’},  
# ’refer’: ’RADIO’,  
# ’type’: ’doppler’}  
f = me.frequency(’lsrk’,’1410MHz’)    # a measured frequency  
print f  
#{’m0’: {’value’: 1410000000.0, ’unit’: ’Hz’},  
# ’refer’: ’LSRK’,  
# ’type’: ’frequency’}  
print me.torestfrequency(f, dp)                   # the corresponding rest frequency  
#{’m0’: {’value’: 1420405751.7854364, ’unit’: ’Hz’},  
# ’refer’: ’REST’,  
# ’type’: ’frequency’}  
 

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