[liversage]

Or 128 bits. FORTRAN has a REAL*16 type (quadruple precision floating point number). I encountered this at university in a physics department that studied non- linear systems also known as chaos theory. Rounding errors can quickly become a problem in these systems.

[gnufx]

> FORTRAN has a REAL16 type

Fortran (note the post-'77 spelling) doesn't. It has KINDs. REALx is a non-standard extension, and there's definitely no requirement to implement 128-bit floating point. I don't know what hardware other than POWER has hardware 128-bit FP (both IEEE and IBM format, with a somewhat painful recent change of the ppc64le ABI default in GCC etc.).

[thanatos519]

GCC also has libquadmath which provides 128-bit floats by sticking 2 64-bit floats together. More than twice as slow, but extra precision just by changing a type and linking the library.

Works great in XaoS, which is where I like my extra precision, but a deep fractal zoom can consume as much precision as you can muster. Imagine a 64kbit-precision Mandelbrot zoom!

[aragilar]

The main use of libquadmath seems to be to support gfortran. GCC/glibc also support _Float128 and <func>f128, which are nominally part of C, but only GCC implements them as far as I know.