title: How to convert column vector into MxN matrix?
body: <p>I am relatively new to C++ and kind of stuck in this problem. I have 999x1 vector of point coordinates and I want to convert it in 333x3 matrix dyanamically. Besides this, I am using different Cpp files for one project so the function which reads the points set is in different file. How to make this matrix and how should I access it in my main code? 
  I tried using <code>vector&lt;vector&lt;float&gt; &gt; Mymatrix</code> thing but you need to specify the rows and column size in this kind of definition which I cannot get until I read the file. If I try to declare above Mymatrix variable in the function which is reading the pointset file, its scope gets limited and I cannot use that Mymatrix in main.cpp.
  Its little bit difficult to write the code here because it has many links with other files. I hope you have got my problem! Please help me in this issue...Thanks in advance!</p>