- #1

- 713

- 5

given a function

*f:R->R*, can anyone explain what is meant when we say that "

*f*has

*compact support*"?

Some sources seem to suggest that it means that

*f*is non-zero only on a closed subset of R.

Other sources say that

*f*vanishes at infinity. This definition seem to contradict the previous: for example the Gaussian is never 0 but does vanish at infinity.

So, where is the misunderstanding?