1.4.1.0 measures.tofrequency

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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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