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63<h1><a class="anchor" name="vector_and_matrix">A very simple tutorial about vectors and matrixes </a></h1>Let's start with a really simple example. Try to complile the following program:<p>
64<div class="fragment"><pre class="fragment"><span class="preprocessor">#include &lt;itpp/itbase.h&gt;</span>
65
66<span class="keyword">using namespace </span>itpp;
67
68<span class="comment">//These lines are needed for use of cout and endl</span>
69<span class="keyword">using</span> std::cout;
70<span class="keyword">using</span> std::endl;
71
72<span class="keywordtype">int</span> main()
73{
74  <span class="comment">//Declare vectors and matricies:</span>
75  vec a, b, c;
76  mat A, B;
77
78  <span class="comment">//Use the function linspace to define a vector:</span>
79  a = linspace(1.0, 2.0, 10);
80
81  <span class="comment">//Use a string of values to define a vector:</span>
82  b = <span class="stringliteral">"0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0"</span>;
83
84  <span class="comment">//Add two vectors:</span>
85  c = a + b;
86
87  <span class="comment">//Print results:</span>
88  cout &lt;&lt; <span class="stringliteral">"a = "</span> &lt;&lt; a &lt;&lt; endl;
89  cout &lt;&lt; <span class="stringliteral">"b = "</span> &lt;&lt; b &lt;&lt; endl;
90  cout &lt;&lt; <span class="stringliteral">"c = "</span> &lt;&lt; c &lt;&lt; endl;
91
92  <span class="comment">//Use a string to define a matrix:</span>
93  A = <span class="stringliteral">"1.0 2.0;3.0 4.0"</span>;
94
95  <span class="comment">//Calculate the inverse of matrix A:</span>
96  B = inv(A);
97
98  <span class="comment">//Print results:</span>
99  cout &lt;&lt; <span class="stringliteral">"A = "</span> &lt;&lt; A &lt;&lt; endl;
100  cout &lt;&lt; <span class="stringliteral">"B = "</span> &lt;&lt; B &lt;&lt; endl;
101
102  <span class="comment">//Exit program:</span>
103  <span class="keywordflow">return</span> 0;
104
105}
106</pre></div><p>
107When you run this program, the output shall look like this<p>
108<div class="fragment"><pre class="fragment">a = [1 1.11111 1.22222 1.33333 1.44444 1.55556 1.66667 1.77778 1.88889 2]
109b = [0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1]
110c = [1.1 1.31111 1.52222 1.73333 1.94444 2.15556 2.36667 2.57778 2.78889 3]
111A = [[1 2]
112 [3 4]]
113B = [[-2 1]
114 [1.5 -0.5]]
115</pre></div><p>
116If this is what you see, then congratulations! You have managed to compile your first it++ program! </div>
117<hr size="1"><address style="text-align: right;"><small>Generated on Wed Jul 1 13:05:56 2009 for mixpp by&nbsp;
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