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measures.tofrequency - Function

1.4.1 convert a doppler type value to a frequency


Description

tofrequency will convert a Doppler type value (e.g. in radio mode) to a frequency. The type of frequency (e.g. LSRK) and a rest frequency (either as a frequency quantity (e.g. qa.constants(’HI’)) or a frequency measure (e.g. me.frequency(’rest’,’5100MHz’)) should be specified

Arguments





Inputs

rf

frequency reference type

allowed:

string

Default:

v0

doppler measure value

allowed:

record

Default:

rfq

rest frequency (frequency measure or freuency quantity)

allowed:

record

Default:

Returns
record

Example

 
 
print "\t----\t tofrequency Ex 1 \t----"  
a=me.doppler(’radio’,’0.4’)  
print a  
#{’m0’: {’value’: 119916983.2, ’unit’: ’m/s’},  
# ’refer’: ’RADIO’,  
# ’type’: ’doppler’}  
print me.tofrequency(’lsrk’,a,qa.constants(’HI’))  
#{’m0’: {’value’: 852243451.07159996, ’unit’: ’Hz’},  
# ’refer’: ’LSRK’,  
# ’type’: ’frequency’}  
 

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