Intel® Fortran Compiler 17.0 Developer Guide and Reference
A REAL(8) or DOUBLE PRECISION constant has more than twice the accuracy of a REAL(4) number, and greater range.
A REAL(8) or DOUBLE PRECISION constant occupies eight bytes of memory. The number of digits that precede the exponent is unlimited, but typically only the leftmost 15 digits are significant.
IEEE* binary64 format is used.
Note that compiler option double-size can affect DOUBLE PRECISION data.
The default KIND for DOUBLE PRECISION is affected by compiler option double-size.
123456789D+5 |
123456789E+5_8 |
+2.7843D00 |
-.522D-12 |
2E200_8 |
2.3_8 |
3.4E7_8 |
-.25D0_2 |
2 is not a valid kind for reals. |
+2.7182812846182 |
No D exponent designator is present; this is a valid single-precision constant. |
123456789.D400 |
Too large for any double-precision format. |
123456789.D-400 |
Too small for any double-precision format. |
Compiler Reference > Data and I/O section: Data Representation