floating point - IEEE 64 and 32 bit float validation in OCaml -


i have string matching following regex \-?[0-9]*\.[0-9]+ supposedly represents ieee floating point number. single or double precision , know type in advance. need check if interpreted valid value in given precission. like:

val is_valid_float: string -> bool val is_valid_double: string -> bool

for double precision numbers, can parse using float_of_string , catch exception. unsure how deal single precision.

@jonathanchan's comments enlightening, more might say.

however, i'm not sure mean validation.

is "1.0000000000000001" valid float?

 val f : string = "1.0000000000000001"  # float_of_string f;;  - : float = 1.  #

there's no exception indicate number can't represented distinct 1.0.

if ignore issues of precision, might not difficult test against representable range string operation.

as @jonathanchan points out, best answer depends on how sure need (and want sure of, exactly).


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