diff --git a/doc/acas_xu.rst b/doc/acas_xu.rst index 81bef8e9ac415a838d5eae427005b8dbc7308de6..cb836f48af6787f6e94ff6593d3490a5a4013155 100644 --- a/doc/acas_xu.rst +++ b/doc/acas_xu.rst @@ -125,11 +125,15 @@ our theory ``ACASXU_P1``. We will need to write down some numerical values. As of now, CAISAR allows writing values using floating-point arithmetic only. Why3 defines a float type -and the relevant arithmetic operations according to the IEEE floating-point +and the relevant arithmetic operations according to the IEEE 754 floating-point standard in a theory, astutely called ``ieee_float``. Specifically, we will import the ``Float64`` sub-theory, that defines everything we need for 64-bit precision floating-point numbers. We thus import it in our theory using the ``use`` keyword. +This currently requires to write exact IEEE 754 floating +point values in the specification file, which is +understandably a setback in terms of usability, but have the +advantage of being unambiguous on the specification. Our file looks like this so far: