1.1.1.0 image.toworld

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image.toworld - Function

1.1.1 Convert from pixel to world coordinate

Description

This function converts between absolute pixel coordinate (0-rel) and world (physical coordinate).

This function is just a wrapper for the Coordsys tool function toworld so see the documentation there for a description of the arguments and more examples.

Arguments


Inputs
value	Absolute pixel coordinate. Numeric vector is allowed. Default is reference pixel.
	allowed:	any
	Default:	variant
format	What type of formatting? String from combination of ’n’ (numeric), ’q’ (quantity), ’m’ (measure), ’s’ (string).
	allowed:	string
	Default:	n
dovelocity	Compute corresponding spectral velocities?
	allowed:	bool
	Default:	True

Returns
record

Example

"""
#
print "\t----\t toworld Ex 1 \t----"
ia.maketestimage(’hcn’,overwrite=true)
w = ia.toworld([10,10], ’n’)
print w
#{’numeric’: array([ 0.00174533, -0.0015708 ])}
w = ia.toworld([10,10], ’nmq’)
print w
#{’measure’: {’direction’: {’m0’: {’unit’: ’rad’,
#                                  ’value’: 0.0017453323593185704},
#                           ’m1’: {’unit’: ’rad’,
#                                  ’value’: -0.0015707969259645381},
#                           ’refer’: ’J2000’,
#                           ’type’: ’direction’}},
# ’numeric’: array([ 0.00174533, -0.0015708 ]),
# ’quantity’: {’*1’: {’unit’: ’rad’, ’value’: 0.0017453323593185704},
#              ’*2’: {’unit’: ’rad’, ’value’: -0.0015707969259645381}}}
ia.close()
#
"""

Convert to a vector of floats and then to a record
holding a vector of floats, a vector of quantities
and a subrecord of measures.

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