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POImplementing '+' operator for std::vector
 

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  1. POImplementing '+' operator for std::vector
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    <p>I'm trying to add support for addition for std::vector. Here's the code I have so far.. The part that doesn't work is the part where I attempt to print the result. I am aware of valarray but I can't get it to work the way that I want (mostly I haven't found an easy way to convert vectors into valarrays).</p> <p>This is the error:</p> <pre><code>../src/VectorOperations.cpp:26:6: error: need 'typename' before 'std::vector&lt;T&gt;::iterator' because 'std::vector&lt;T&gt;' is a dependent scope </code></pre> <hr> <pre><code>class VectorOperations { public: //Vector Operations std::vector&lt;double&gt; logv(std::vector&lt;double&gt; first); std::vector&lt;double&gt; raiseTo(std::vector&lt;double&gt; first, int power); std::vector&lt;double&gt; xthRoot(std::vector&lt;double&gt; first, int xth); double sumv(std::vector&lt;int&gt; first); std::vector&lt;double&gt; operator + ( const std::vector&lt;double&gt; &amp; ) const; std::vector&lt;double&gt; operator - ( const std::vector&lt;double&gt; &amp; ) const; std::vector&lt;double&gt; operator * ( const std::vector&lt;double&gt; &amp; ) const; std::vector&lt;double&gt; operator / ( const std::vector&lt;double&gt; &amp; ) const; }; template &lt;typename T&gt; std::vector&lt;T&gt; operator+(const std::vector&lt;T&gt;&amp; a, const std::vector&lt;T&gt;&amp; b) { assert(a.size() == b.size()); std::vector&lt;T&gt; result; result.reserve(a.size()); std::transform(a.begin(), a.end(), b.begin(), std::back_inserter(result), std::plus&lt;T&gt;()); std::cout&lt;&lt;"Results from addition follow: \n"; //HERE'S THE PROBLEM: I WANT TO PRINT OUT BUT I GET ERRORS for(std::vector&lt;T&gt;::iterator it = a.begin(); it != a.end(); ++it) { /* std::cout &lt;&lt; *it; ... */ } return result; } </code></pre>
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    1. COWell.. you have <double> in the class method declaration yet you use <T> for the method definition. Rest is up to you to figure out.
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      1. USRapptz
    2. CODoesn't the compiler error tell you *exactly* what to do?
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      1. USus2012
    3. COAlso, you're defining a free function. `class VectorOperations` is completely irrelevant here!
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      1. USJohnsyweb
 

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