Re: Converting decimal to/from IEEE hex format

*To*: mathgroup at smc.vnet.net*Subject*: [mg71237] Re: Converting decimal to/from IEEE hex format*From*: "Ray Koopman" <koopman at sfu.ca>*Date*: Sat, 11 Nov 2006 03:38:55 -0500 (EST)*References*: <ej1pgr$ds0$1@smc.vnet.net>

Robert wrote: > Can anyone tell me how to convert a number to/from the corresponding > IEEE hex floating-point representation in either 32 or 64 bits in > Mathematica? For > example, I would want to convert 1.0 into 3F800000 (32-bit) or > 3FF0000000000000 (64-bit), and vice-versa. (When converting from > decimal to hex, if the number is not exactly representable, I would > want the nearest floating-point number.) Thanks, Robert In[1]:= ieee64[x_] := StringJoin[ StringTake["0123456789ABCDEF",{#+1}]& /@ Join[IntegerDigits[2048*Boole@Negative@x+1022+#[[2]],16,3], FromDigits[#,2]&/@Partition[Rest@#[[1]],4]]& @ RealDigits[N@x,2,53] ] In[2]:= ieee64[-1.75] Out[2]= BFFC000000000000