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interpolation - Requiring NumericQ in Pure Function


Potential duplicate, but doesn't seem to solve my problem: Using patterns in pure functions


I have a function that returns an InterpolatingFunction, and it works exactly the way I needed for passing to NIntegrate etc.: if I pass on a symbolic argument, the function returns itself; if the argument is numeric, it evaluates and gives a number.


func := Module[{...}, ... (y /. First@NDSolve[{y[1] == 1, y'[x] == x}, y, {x, -1, 1}])]
func[x] (* gives InterpolatingFunction[(-1. 1.),<>](x) *)
func[0.5] (* gives 0.625 *)


I need a slightly modified behavior: the returned function should return 0 if outside the range instead of attempting to interpolate. Seems easy enough:


func := Module[{interpolation,...}, ...
interpolation = (y /. First@NDSolve[{y[1] == 1, y'[x] == x}, y, {x, -1, 1}]);
Function[x,If[Not@IntervalMemberQ[Interval[interpolation[[1, 1]]], x], 0,
interpolation[x]]]]
func[0.5] (* gives 0.625 *)
func[2] (* gives 0 since it's outside the interpolation interval *)
func[x] (* gives 0!! *)

How can one mimic the behavior of InterpolatingFunction such that func[x] for non-numeric x gives something like Function[<>](x) instead?





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