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POValues not written to vector
 

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  1. POValues not written to vector
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    <p>I'm trying to read pairs values from a file in the constructor of an object.</p> <p>The file looks like this:</p> <pre><code>4 1 1 2 2 3 3 4 4 </code></pre> <p>The first number is number of pairs to read.</p> <p>In some of the lines the values seem to have been correctly written into the vector. In the next they are gone. I am totally confused</p> <pre><code>inline BaseInterpolator::BaseInterpolator(std::string data_file_name) { std::ifstream in_file(data_file_name); if (!in_file) { std::cerr &lt;&lt; "Can't open input file " &lt;&lt; data_file_name &lt;&lt; std::endl; exit(EXIT_FAILURE); } size_t n; in_file &gt;&gt; n; xs_.reserve(n); ys_.reserve(n); size_t i = 0; while(in_file &gt;&gt; xs_[i] &gt;&gt; ys_[i]) { // this line prints correct values i.e. 1 1, 2 2, 3 3, 4 4 std::cout &lt;&lt; xs_[i] &lt;&lt; " " &lt;&lt; ys_[i] &lt;&lt; std::endl; // this lines prints xs_.size() = 0 std::cout &lt;&lt; "xs_.size() = " &lt;&lt; xs_.size() &lt;&lt; std::endl; if(i + 1 &lt; n) i += 1; else break; // this line prints 0 0, 0 0, 0 0 std::cout &lt;&lt; xs_[i] &lt;&lt; " " &lt;&lt; ys_[i] &lt;&lt; std::endl; } // this line prints correct values i.e. 4 4 std::cout &lt;&lt; xs_[i] &lt;&lt; " " &lt;&lt; ys_[i] &lt;&lt; std::endl; // this lines prints xs_.size() = 0 std::cout &lt;&lt; "xs_.size() = " &lt;&lt; xs_.size() &lt;&lt; std::endl; } </code></pre> <p>The class is defined thus:</p> <pre><code>class BaseInterpolator { public: ~BaseInterpolator(); BaseInterpolator(); BaseInterpolator(std::vector&lt;double&gt; &amp;xs, std::vector&lt;double&gt; &amp;ys); BaseInterpolator(std::string data_file_name); virtual int interpolate(std::vector&lt;double&gt; &amp;x, std::vector&lt;double&gt; &amp;fx) = 0; virtual int interpolate(std::string input_file_name, std::string output_file_name) = 0; protected: std::vector&lt;double&gt; xs_; std::vector&lt;double&gt; ys_; }; </code></pre>
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    1. This table or related slice is empty.
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    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
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    2. PO
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    3. PO
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    1. VO
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      1. POValues not written to vector
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      1. POValues not written to vector
      1. This table or related slice is empty.
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    1. This table or related slice is empty.
 

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