shithub: mc

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Add fltXXfromuintXX to ancillary math script.

--- a/lib/math/ancillary/ulp.gp

+++ b/lib/math/ancillary/ulp.gp

@@ -25,3 +25,25 @@

 { err64(x, y) =

         return(abs(x-y)/ulp64(x));

 }

+

+{ flt32fromuint32(a) = my(n, e, s);

+        n = bitand(a, 0x80000000) != 0;

+        e = bitand(a, 0x7f800000) >> 23;

+        s = bitand(a, 0x007fffff);

+

+        if(e != 0, s = bitor(s, 0x00800000),);

+        s = s * 2.0^(-23);

+        e = e - 127;

+        return((-1)^n * s * 2^(e));

+}

+

+{ flt64fromuint64(a) = my(n, e, s);

+        n = bitand(a, 0x8000000000000000) != 0;

+        e = bitand(a, 0x7ff0000000000000) >> 52;

+        s = bitand(a, 0x000fffffffffffff);

+

+        if(e != 0, s = bitor(s, 0x0010000000000000),);

+        s = s * 2.0^(-52);

+        e = e - 1023;

+        return((-1)^n * 2^(e) * s);

+}