Quick question about invalid operands!

This is a discussion on Quick question about invalid operands! within the C Programming forums, part of the General Programming Boards category; Working on a program right now but I left my book at home so I can't look this up. Does ...

  1. #1
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    Quick question about invalid operands!

    Working on a program right now but I left my book at home so I can't look this up. Does anyone know how to fix this off the top of their head? I was thinking about using 'atoi' but I can't remember how it works exactly.

    "invalid operands of types `double' and `double' to binary `operator^' "

    is what is says to me. :[

  2. #2
    Deathray Engineer MacGyver's Avatar
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    ^ is bitwise XOR, which I imagine you may have been thinking is the way to raise a number to an arbitrary power. If that is the case, use the pow() function in math.h.

    atoi() has nothing to do with this, and is a rather silly suggestion. Don't confuse strings with math or bitwise operations.

    If you are trying to bitwise XOR two doubles, whatever you're doing is probably very weird and wrong.

  3. #3
    C++まいる!Cをこわせ! Elysia's Avatar
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    Simple.
    Code:
    	float f1 = 1.0f, f2 = 2.0f, f3;
    	double d1 = 1, d2 = 2, d3;
    	int i1 = 1, i2 = 2, i3;
    	f3 = f1 | f2; // C2296 and C2297
    	d3 = d1 | d2; // C2296 and C2297
    	i3 = i1 | i2;
    	f3 = f1^f2; // C2296 and C2297
    	d3 = d1^d2; // C2296 and C2297
    	i3 = i1^i3;
    Why you ask? Type must be an integer, not a floating point.

  4. #4
    and the Hat of Guessing tabstop's Avatar
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    I don't think operator^ is what you think it is, unless you want to bitwise-XOR two doubles together. atoi takes a string and returns the integer it represents.

    I'm guessing you want to raise to a power? If so, use pow().

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