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image.pixelvalue - Function

1.1.1 Get value of image and mask at specified pixel coordinate


Description

This function gets the value of the image and the mask at the specified pixel coordinate. The values are returned in a record with fields ’value’, ’mask’ and ’pixel’. The value is returned as a quantity, the mask as a Bool (T is good). The ’pixel’ field holds the actual pixel coordinate used.

If the specified pixel coordinate is off the image, ”{}” is returned.

Excessive elements in pixel are silently discarded. Missing elements are given the (nearest integer) value of the reference pixel. This is reflected in the output record ’pixel’ field.

Arguments





Inputs

pixel

Pixel coordinate

allowed:

intArray

Default:

-1

Returns
record

Example

 
 
"""  
#  
print "\t----\t pixelvalue Ex 1 \t----"  
ia.maketestimage();  
ia.pixelvalue()  
#{’mask’: True,  
# ’pixel’: array([55, 37]),  
# ’value’: {’unit’: ’Jy/beam’, ’value’: 2.5064315795898438}}  
print ia.pixelvalue([-1,-1])  
# {}  
print ia.pixelvalue([9])  
#{’mask’: True,  
# ’pixel’: array([ 9, 37]),  
# ’value’: {’unit’: ’Jy/beam’, ’value’: 0.14012207090854645}}  
print ia.pixelvalue([9,9,9])  
#{’mask’: True,  
# ’pixel’: array([9, 9]),  
# ’value’: {’unit’: ’Jy/beam’, ’value’: -0.45252728462219238}}  
ia.close()  
#  
"""  
 

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