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coordsys.toworldmany - Function

1.1.3 Convert many absolute pixel coordinates to numeric world


Description

This function converts many absolute pixel coordinates to world coordinates. It exists so you can efficiently make many conversions (which would be rather slow if you did them all with toworld). Because speed is the object, the interface is purely in terms of numeric matrices, rather than being able to produce strings and quanta etc. like toworld can.

The units of the output world values are the native units given by function units.

Arguments





Inputs

value

Absolute pixel coordinates

allowed:

variant

Default:

Returns
record

Example

 
 
"""  
#  
print "\t----\t toworldmany Ex 1 \t----"  
csys = cs.newcoordsys(direction=T, spectral=T)    # 3 axes  
rp = csys.referencepixel()[’numeric’];            # reference pixel  
pabs = ia.makearray(0,[3,100])              # 100 conversions each of length 3  
for i in range(3):  
  for j in range(100):  
    pabs[i][j] = rp[i]  
for ioff in range(100):                     # offset for third axis  
  pabs[2][ioff] += ioff;                    # Make spectral axis values change  
wabs  = csys.toworldmany (pabs)[’numeric’]; # Convert  
print wabs[0][0], wabs[1][0], wabs[2][0]    # First absolute pixel coordinate  
#0.0 0.0 1415000000.0  
print wabs[0][99], wabs[1][99], wabs[2][99] # 100th absolute pixel coordinate  
#0.0 0.0 1415099000.0  
#  
"""  
 

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