A map 
is called constant with constant value 
if 
for all 
,
i.e., if all elements of 
are sent to same element 
of 
.
Constant Map
See also
Constant Function, Identity Map, Zero MapThis entry contributed by Margherita Barile
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Cite this as:
Barile, Margherita. "Constant Map." From MathWorld--A Wolfram Web Resource, created by Eric W. Weisstein. https://mathworld.wolfram.com/ConstantMap.html