Determines whether an input is a number or string.
Ans - the number or string to examine
Ans - 1 if the input is a number, 0 if it is a string
A, B [,∟A, ∟B if input is a string]
TI-83/84/+/SE
bfr
URL: [http://www.unitedti.org/forum/index.php?showtopic=9191]
:DelVar AFor(B,1,1
:Ans->A
:Ans->B
:A=B
If Ans is a string, it is stored to ∟A and ∟B. A remains 0, B remains 1, and A=B returns false. If Ans is a number, it is stored into both A and B, thus A=B returns true.
The For( command is used to avoid updating Ans. If this routine is used in a larger program and the input can be stored into a more permanent variable, For(B,1,1 can become 1->B. If this is not possible, the For( statement should have an End added.
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