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##### measures.expand - Function

1.4.1 expand n positions to n*(n-1)/2 baselines

Description

expand calculates the differences between a series of given measure values: it calculates baseline values from position values. The returned value is a measure, but the value of the optional output variable xyz will be set to an array of values.

Arguments

 Outputs xyz uvw (quantity array) allowed: record Default: Inputs v measure (baseline, position or uvw measure) allowed: record Default:
Returns
record

Example

print "\t----\t expand Ex 1 \t----"
b=me.baseline(’itrf’, qa.quantity([10, 20, 30], ’m’), qa.quantity([10, 20, 30], ’m’), qa.quantity([0, 0, 0], ’m’))
print me.expand(b)
me.expand(b)

#{’return’: {’m0’: {’unit’: ’rad’,
#                   ’value’: array([ 0.78539816,  0.78539816,  0.78539816])},
#            ’m1’: {’unit’: ’rad’, ’value’: array([ 0.,  0.,  0.])},
#            ’m2’: {’unit’: ’m’,
#                   ’value’: array([ 14.14213562,  28.28427125,  14.14213562])},
#            ’refer’: ’ITRF’,
#            ’type’: ’baseline’},
# ’xyz’: {’unit’: ’m’,
#         ’value’: array([ 10.,  10.,   0.,  20.,  20.,   0.,  10.,  10.,   0.])}}

print me.expand(b)[’xyz’][’value’]

#[ 10.  10.   0.  20.  20.   0.  10.  10.   0.]

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