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POC++ Matrix Class - Suggestions
 

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    <p>I am trying to build a templated Matrix class in C++. Below is its implementation. I implemented two operators +,+= as of now just to give an idea on how it will look and I thought it would be best to ask for feedback before I proceed any further.</p> <p>The whole implementation is public and also there are no explicit bound/error checks, this is because its not meant to be a full fledged matrix library and hence avoided unnecessary code.</p> <p>It would be very helpful if someone could comment on it and may be suggest a few improvements or suggestions.</p> <p>Thank you.</p> <pre><code>template&lt;class T&gt; class Matrix { public: int r,c; vector&lt; vector&lt; T &gt; &gt;mat; Matrix() {} // Constructor to set the size of the matrix Matrix(int _r,int _c) { r=_r;c=_c; mat.resize(r); for(int i=0;i&lt;r;i++) mat[i].resize(c); } // Constructor to build a matrix from a C 2d array // Pointer to the first element is passed (&amp;arr[0][0]) Matrix(T *arr,int _r,int _c) { r=_r;c=_c; mat.resize(r); for(int i=0;i&lt;r;i++) for(int j=0;j&lt;c;j++) mat[i].push_back(arr[i*c+j]); } template&lt;typename U&gt; Matrix&lt;T&gt;&amp; operator +=(const Matrix&lt;U&gt;&amp;M) { for(int i=0;i&lt;r;i++) for(int j=0;j&lt;c;j++) mat[i][j]+=static_cast&lt;T&gt;(M.mat[i][j]); return *this; } template&lt;typename U&gt; Matrix&lt;T&gt; operator +(const Matrix&lt;U&gt;&amp;M) { Matrix&lt;T&gt;tmp=*this; return tmp+=M; } }; template&lt;typename T&gt; istream&amp; operator &gt;&gt;(istream &amp;in,Matrix&lt;T&gt;&amp;M) { in&gt;&gt;M.r&gt;&gt;M.c; Matrix&lt;T&gt;tmp(M.r,M.c); for(int i=0;i&lt;M.r;i++) for(int j=0;j&lt;M.c;j++) in&gt;&gt;tmp.mat[i][j]; M=tmp; return in; } template&lt;typename T&gt; ostream&amp; operator &lt;&lt;(ostream &amp;out,Matrix&lt;T&gt;M) { for(int i=0;i&lt;M.r;i++) { for(int j=0;j&lt;M.c;j++) cout&lt;&lt;M.mat[i][j]&lt;&lt;" "; cout&lt;&lt;endl; } return out; } </code></pre> <p>EDIT: Thank you all for the suggestions. </p> <p>I just have one small question, say I do want to implement error checking (ex: checking for bounds,valid arguments etc..) however I do want the provide user with an option to disable error checking completely, is there any good way to implement this ? What I need is something like example:`ios_base::sync_with_stdio(0);. Thanks again.</p>
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