No.

# Matrices as Data Types

Here is a scheme for matrix data types. To create a matrix type, fill each blank with one of the choices.

```    .
.
.
4
3
2                row
1                column
______ dimensional _______ matrix
```

For example "3 dimensional column matrix", or "4 dimensional row matrix". In a programming language, you might declare a type for each of the matrix types. For example, in C:

```typedef double colMatrix2;
typedef double colMatrix3;
...

typedef double rowMatrix2;
typedef double rowMatrix3;
...
```

Then you would write an equality-testing function for each type:

```int equalCM2( colMatrix2 x, colMatrix2 y )
{
return x == y && x == y ;
}

int equalCM3( colMatrix3 x, colMatrix3 y )
{
return x == y && x == y && x == y;
}

...
```

This gets awfully tedious, so usually you create a more general data type and hope that the user will keep row matrices and column matrices straight without help from the compiler. An elegant solution is to use object-oriented programming.

Since for us vectors will always be represented with column matrices, we will use only a few types.

### QUESTION 10: Are the following two column matrices equal?

( 2, -1 )T
( 2.0, -1.0 )T