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FirstNonZero

the first non-zero entry in a vector
Syntax 

FirstNonZero(V:VECTOR):POLY

Description
This function returns the first non-zero entry of V. If it is handed a zero vector then an error is signalled.

Example 
  Use R ::= QQ[x,y,z];
  V := Vector(0,0,x^2+yz,0,z^2);
  FirstNonZero(V);
x^2 + yz
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See Also