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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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