>>se3 = strel('square',3)
Neighborhood:
     1     1     1
     1     1     1
     1     1     1
>> se3 = strel('line',3 , 45)
Neighborhood:
     0     0     1
     0     1     0
     1     0     0
>> se3 = strel('line',3 , 90)

Neighborhood:
     1
     1
     1

>> nm=[3 5]
>> se3 = strel('rectangle',nm)

Neighborhood:
     1     1     1     1     1
     1     1     1     1     1
     1     1     1     1     1


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