1.1.1.0 image.topixel

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image.topixel - Function

1.1.1 Convert from world to pixel coordinate
Description

This function converts from absolute world to pixel coordinate (0-rel). The world coordinate can be provided in many formats (numeric, string, quantum etc.) via the argument value. These match the output formats of function toworld.

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

Arguments


Inputs
value	Absolute world coordinate, Numeric vector, vector of quantities or record. Default is reference value.
	allowed:	any
	Default:	variant

Returns
anyrecord

Example

"""
#
print "\t----\t topixel Ex 1 \t----"
ia.maketestimage();
w = ia.toworld([10,10], ’n’) # Numeric vector
ia.topixel(w)
#{’ar_type’: ’absolute’,
# ’numeric’: array([10., 10.]), ’pw_type’: ’pixel’}
w = ia.toworld([10,10], ’m’) # Record of measures
ia.topixel(w)
#{’ar_type’: ’absolute’,
# ’numeric’: array([10., 10.]), ’pw_type’: ’pixel’}
ia.close()
#
"""

Convert a pixel coordinate to world as floats and then back to pixel. Do the same with the world coordinate formatted as measures instead.

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