Re: encoding a float

From:
Fei Liu <feiliu@aepnetworks.com>
Newsgroups:
comp.lang.c++
Date:
Tue, 27 Mar 2007 11:08:40 -0400
Message-ID:
<eubflp$9nk$1@aioe.org>
hurcan solter wrote:

Hi all, I am trying to convert a float value to a octet stream for
transmission, I came up with solution like

float deneme=3.14156789;
    float deneme2=0.0;
        vector<unsigned char> vec; //this is my buffer can con contain
other things besides this float

    int* val=reinterpret_cast<int*>(&deneme); // gives me jeebies
    vec.push_back((unsigned char) ((*val >> 24) & 0xFF ));
    vec.push_back((unsigned char) ((*val >> 16) & 0xFF ));
    vec.push_back((unsigned char) ((*val >> 8) & 0xFF ));
    vec.push_back((unsigned char) ((*val >> 0) & 0xFF ));
        int val2=0;
    int _pos=0;
    val2+= ((int)vec[_pos++] & 0xFF) << 24;
    val2+= ((int)vec[_pos++] & 0xFF) << 16;
    val2+= ((int)vec[_pos++] & 0xFF) << 8;
    val2+= ((int)vec[_pos++] & 0xFF) << 0;
    deneme2=*reinterpret_cast<float*>(&val2); //ditto

      it works, but i am not sure that this is the Right Way to do, I
wonder if there is
     a safer or cleaner way? I tried memcpy to treat the vector as if
an array it didn't
     work out well( although, It should work right?)
    Any pointers would be greatly appreciated...
    hurcan


Did you look into more general framework such as soap or yaml? Boost
also has a primitive serialization/deserialization framework.

Fei

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