public static void addEquals( DMatrix2 a , DMatrix2 b ) {
        a.a1 += b.a1;
        a.a2 += b.a2;
    }
public static void addEquals ( DMatrix2 a , DMatrix2 b ) { a . a1 += b . a1 ; a . a2 += b . a2 ; }
<p>Performs the following operation:<br>
<br>
a = a + b <br>
a<sub>i</sub> = a<sub>i</sub> + b<sub>i</sub> <br>
</p>

@param a A Vector. Modified.
@param b A Vector. Not modified.