Berkeley CSUA MOTD:Entry 14688
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2025/07/12 [General] UID:1000 Activity:popular
7/12    

1998/9/28-29 [Computer/SW/Languages/C_Cplusplus, Computer/SW/Languages] UID:14688 Activity:kinda low
9/27    I'm trying to output the binary representation of a ieee754 double
        in c/c++.  I'm using union { double x; long y; } and then
        shifting iteratively with a value.y >> i and then masking it with
        a value.y & 0x1 but that doesn't seem to work.  Any suggestions?
        \_ first problem:  a double is probably larger in size than a long
           on your architecture.  are you sure your compiler is doing ieee754
           doubles?  what you described is very dependent on what you're using.
        \_ printf("%08x\n", * (long *) &x);
        \_ printf("%qx\n", *(long long *) &x) is what you want on soda, where
           a double is 64 bits and a long is 32.  Other machines will vary.
        \_ Why not use a char array in your union?  That way you only have
           the length of the double to worry about.
           \_And the endian-ness.
2025/07/12 [General] UID:1000 Activity:popular
7/12    

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