And that's all I was after

If it matters to you (and it may conceivably not), that seems not quite the same as the split that the hardware double-double implementations produce.
On my double-double (PowerPC) box, for your given 32-digit value of
3.1415926535897932384626433832795
the 2 doubles would there round out as
3.14159265358979e+000 and 1.22464679914735e-016
with actual hex representations of
0x1.921fb54442d18p+1 and 0x1.1a62633145c07p-53.

Those 2 hex values concatenate to the correct 107-bit representation of the original value: 
0.11001001000011111101101010100010001000010110100011000010001101001100
+010011000110011000101000101110000000111E2

[download]
Cheers,
Rob

In reply to Re^5: Math::BigFloat to native double? by syphilis
in thread Math::BigFloat to native double? by BrowserUk

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