Re: 80 bit precision ?

Terry Reedy a écrit :
> [...]
> Last I read, in CPython, the float type encapsulates a C double.
> So, does any C compiler implements doubles as 80 bit floats?

I seriously doubt it.

> Or, if it has 64 bit
> doubles and 80 bit long doubles, are the latter transparently
> substitutible for the former, so that you could change Python's
> float declaration and have everything work as expected? (I an
> not sure of either.)

Mmmmmm ... the python C code implementing the math module is
probably not that polymorphic <wink>. Even a call to "sqrt"
does not work as expected if the argument is a long double.
"sqrtl" should be use instead.

Cheers,

SB

.

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