How do I set up a function's options so that the function returns its results in either the exact form (default) or with N decimal places?
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1 Answer
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fun[x_, r_Integer: 0] := x + 1 // If[r == 0, #, N[#, Length@IntegerDigits@IntegerPart@# + r]] & fun[1] 2
fun[1, 4] 2.0000
fun[1/2] 3/2
fun[1/2, 1] 1.5
If you need this also for other functions you could define
rounder[x_, 0] := x rounder[x_, r_] := N[x, Length@IntegerDigits@IntegerPart@x + r] and now simply
foo[x_, r_Integer: 0] := rounder[x + 2, r] 
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