REPRESENT

( c-addr u -- n flag1 flag2 ) ( F: r -- ) or ( r c-addr u -- n flag1 flag2 )

At c-addr, place the character-string external representation of the significand of the floating-point number r. Return the decimal-base exponent as n, the sign as flag1 and "valid result" as flag2. The character string shall consist of the u most significant digits of the significand represented as a decimal fraction with the implied decimal point to the left of the first digit, and the first digit zero only if all digits are zero. The significand is rounded to u digits following the "round to nearest" rule; n is adjusted, if necessary, to correspond to the rounded magnitude of the significand. If flag2 is true then r was in the implementation-defined range of floating-point numbers. If flag1 is true then r is negative.

An ambiguous condition exists if the value of BASE is not decimal ten.

When flag2 is false, n and flag1 are implementation defined, as are the contents of c-addr. Under these circumstances, the string at c-addr shall consist of graphic characters.

See:

Rationale:

This word provides a primitive for floating-point display. Some floating-point formats, including those specified by IEEE-754, allow representations of numbers outside of an implementation-defined range. These include plus and minus infinities, denormalized numbers, and others. In these cases we expect that REPRESENT will usually be implemented to return appropriate character strings, such as "+infinity" or "nan", possibly truncated.

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