1.1.3.0 coordsys.toabsmany

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coordsys.toabsmany - Function

1.1.3 Convert many numeric relative coordinates to absolute

Description

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

When dealing with world coordinates, the units of the numeric values must be the native units, given by function units.

Arguments


Inputs
value	Relative coordinates
	allowed:	any
	Default:	variant
isworld	Is coordinate world or pixel? Default is unset.
	allowed:	int
	Default:	-1

Returns
record

Example

"""
#
print "\t----\t toabsmany Ex 1 \t----"
csys = cs.newcoordsys(direction=T, spectral=T)    # 3 axes
rv = csys.referencevalue();                 # reference value
w = csys.torel(rv)                          # make relative
inc = csys.increment();                     # increment
off=[]
for idx in range(100):
  off.append(inc[’numeric’][2]*idx)         # offset for third axis
wrel = ia.makearray(0,[3,100])              # 100 conversions each of length 3
for i in range(3):
  for j in range(100):
    wrel[i][j]=w[’numeric’][i]
for j in range(100):
  wrel[2][j] += off[j]                      # Make spectral axis values change
wabs  = csys.toabsmany (wrel, T)[’numeric’] # Convert
print wabs[0][0],wabs[1][0],wabs[2,0]       # First absolute coordinate
#0.0 0.0 1415000000.0
print wabs[0][99],wabs[1][99],wabs[2][99]   # 100th absolute coordinate
#0.0 0.0 1415099000.0
#
"""

This example uses world coordinates.

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