Thread: Problem with double conversion to char*

  1. #1
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    Problem with double conversion to char*

    Hi I am working with Opencv and it has a function cvGetCaptureProperty which returns a double. There is one case where I need to convert the double into char* and the sample code is provided below. The problem is that, the conversion does not return any value.


    double f = cvGetCaptureProperty(capture, CV_CAP_PROP_FOURCC);
    char* fourcc = (char*) (&f);
    cout<<"\nf_double: "<<f<<"\nfourcc: "<<fourcc<<"\n";

    Output: f has a value but fourcc has no value.
    Any help will be appreciated. Thanks.

    Regards
    Luhfluh

  2. #2
    C++まいる!Cをこわせ!
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    Use sprintf. You should probably also read up on strings and pointers to understand why what you do doesn't work.
    Quote Originally Posted by Adak View Post
    io.h certainly IS included in some modern compilers. It is no longer part of the standard for C, but it is nevertheless, included in the very latest Pelles C versions.
    Quote Originally Posted by Salem View Post
    You mean it's included as a crutch to help ancient programmers limp along without them having to relearn too much.

    Outside of your DOS world, your header file is meaningless.

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    Quote Originally Posted by Elysia View Post
    Use sprintf. You should probably also read up on strings and pointers to understand why what you do doesn't work.
    Hi, thanks for the heads up. Figured it out after some strings and pointer notes, much appreciated

  4. #4
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    That statement will print the location of f; for its contents use *fourcc.

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