1.1.3.0 coordsys.toworld

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coordsys.toworld - Function

1.1.3 Convert from absolute pixel coordinate to world

Description

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

If you supply fewer pixel values than there are axes in the Coordinate System, your coordinate vector will be padded out with the reference pixel for the missing axes. Excess values will be silently ignored.

You may ask for the world coordinate in all of the formats described in the discussion regarding the formatting possibilities available via argument format.

Arguments


Inputs
value	Absolute pixel coordinate. Default is reference pixel.
	allowed:	any
	Default:	variant
format	Format string: combination of ”n”, ”q”, ”s”, ”m”
	allowed:	string
	Default:	n

Returns
record

Example

"""
#
print "\t----\t toworld Ex 1 \t----"
csys = cs.newcoordsys(direction=True, spectral=True)
print csys.toworld([-3,1,1], ’n’)
#{’ar_type’: ’absolute’, ’pw_type’: ’world’,
# ’numeric’: array([  3.00000051e+00,   1.00000001e+00,   1.41500100e+09])}
print csys.toworld([-3,1,1], ’q’)
#{’ar_type’: ’absolute’, ’pw_type’: ’world’,
# ’quantity’: {’*1’: {’value’: 3.0000005076962117, ’unit’: "’"},
#              ’*2’: {’value’: 1.0000000141027674, ’unit’: "’"},
#              ’*3’: {’value’: 1415001000.0, ’unit’: ’Hz’}}}
print csys.toworld([-3,1,1], ’m’)
#{’ar_type’: ’absolute’, ’pw_type’: ’world’, ’measure’:
# {’spectral’: {’radiovelocity’: {’type’: ’doppler’, ’m0’: {’value’: 1140733.0762829871, ’unit’: ’m/s’}, ’refer’: ’RADIO’},
#             ’opticalvelocity’: {’type’: ’doppler’, ’m0’: {’value’: 1145090.2316004676, ’unit’: ’m/s’}, ’refer’: ’OPTICAL’},
#                 ’frequency’: {’type’: ’frequency’, ’m0’: {’value’: 1415001000.0, ’unit’: ’Hz’}, ’refer’: ’LSRK’},
#                ’betavelocity’: {’type’: ’doppler’, ’m0’: {’value’: 1142903.3485169839, ’unit’: ’m/s’}, ’refer’: ’TRUE’}},
# ’direction’: {’type’: ’direction’, ’m1’: {’value’: 0.0002908882127680503, ’unit’: ’rad’},
#                                    ’m0’: {’value’: 0.00087266477368000634, ’unit’: ’rad’}, ’refer’: ’J2000’}}}
print csys.toworld([-3,1,1], ’s’)
#{’ar_type’: ’absolute’, ’pw_type’: ’world’,
# ’string’: array([’00:00:12.00000203’, ’+00.01.00.00000085’, ’1.41500100e+09 Hz’], dtype=’|S19’)}
#
"""

Example

"""
#
print "\t----\t toworld Ex 2 \t----"
csys = cs.newcoordsys (stokes="I V", linear=2)
print csys.toworld([0,1,2], ’s’)
#{’ar_type’: ’absolute’, ’pw_type’: ’world’,
# ’string’: array([’I’, ’1.00000000e+00 km’, ’2.00000000e+00 km’],
#      dtype=’|S18’)}
print csys.toworld([0,1,2], ’m’)
#{’ar_type’: ’absolute’, ’pw_type’: ’world’,
# ’measure’: {’stokes’: ’I’, ’linear’: {’*1’: {’value’: 1.0, ’unit’: ’km’},
#                                       ’*2’: {’value’: 2.0, ’unit’: ’km’}}}}
print csys.toworld([0,1,2], ’q’)
#{’ar_type’: ’absolute’, ’pw_type’: ’world’,
# ’quantity’: {’*1’: {’value’: 1.0, ’unit’: ’’},
#              ’*2’: {’value’: 1.0, ’unit’: ’km’},
#              ’*3’: {’value’: 2.0, ’unit’: ’km’}}}
#
"""

Example

"""
#
print "\t----\t toworld Ex 3 \t----"
csys = cs.newcoordsys (spectral=True, linear=1)
print cs.toworld([0,1,2], ’q’)
#{’ar_type’: ’absolute’, ’pw_type’: ’world’,
# ’quantity’: {’*1’: {’value’: 1415000000.0, ’unit’: ’Hz’},
# ’*2’: {’value’: 1.0, ’unit’: ’km’}}}
#
"""

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