HUGE intrinsic function

Standard: F77 F90 F95 F2003 F2008 F2018 Example program


HUGE ( X )

X : Integer or Real;
Result : Scalar, same type and kind as X.


This function returns the largest “model number” for the type and kind of X.

This is an inquiry function, so X need not be defined; indeed, it is permitted to be disassociated, unallocated, or absent.

The model for integer type is as a sign together with DIGITS(X) digits of radix RADIX(X); the HUGE value is therefore DIGITS(X) digits that are all equal to RADIX(X)−1. For example, the model for 8-bit integers has 7 digits of radix 2, and therefore HUGE(0_int8) is equal to B'01111111'.

The model for real type is that it may be zero or a signed fraction between 1 and 1/RADIX(X) consisting of DIGITS(X) digits, multiplied by an exponent RADIX(X)**e with MINEXPONENT(X)≤e≤MAXEXPONENT(X). Thus the largest model number is the value obtained for the fraction just less than 1 (i.e. all digits set to RADIX(X)−1) and with e equal to MAXEXPONENT(X).

Note that HUGE(X) is not necessarily the largest possible value for X; for example, with IEEE floating-point, the largest possible value is +∞, which is infinitely bigger than HUGE(X). It is, however, likely to be the largest value for which the full precision of DIGITS(X) of radix RADIX(X) is available.


DIGITS intrinsic function, EPSILON intrinsic function, INTEGER type, MAXEXPONENT intrinsic function, MINEXPONENT intrinsic function, RADIX intrinsic function, REAL type, TINY intrinsic function