Tell what is encoded in a float, given its HEX bytes

dc -e"16i?dsH0sq2d17^ss8^dse2/1-stdlsle*/2*2B+an[[ FP Indef.]n]sQ[dls2//2%_2*53+an[NaN]ndle4*1-ls2/*=Q2Q]sN[1sqdls%0<N[oo]n]sMdls/le%dsdle1-=M[[]pq]sPlq1=P[r+0]s0ldd1r0=0lHls%rls*+sS2r^Alt4*^*lS*2lt^/ls/dsSZlt4*-1-sFlsZ1+klSdArZ1-^/dn0=P[e]nlFp"
It handles all possible combination of the hex bytes, including NaNs, Infinities, Normalized and Subnormal Numbers... This crazy DC stuff spent me a few days to write, optimize, polish and squeeze so that it works within the tight 255 character bound... You can modify it easily for other IEEE754 numbers, say, half, double, double-extended, quadruple (I hope someone will find this useful and submit more dc code to commandlinefu!)
Sample Output
$> echo "7F7FFFFF" | dc -e"<this stuff>"
+3.40282346e38
$> echo "7F800000" | dc -e"<this stuff>"
+oo
$> echo "7FC00000" | dc -e"<this stuff>"
+QNaN
$> echo "FFC00000" | dc -e"<this stuff>"
-QNaN FP Indef.

1
By: billyauhk
2011-07-27 18:55:20

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What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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