### Related

m:[[1,2],[3,4]];

matrixp(m);

Calculate

##### matrixp-minor

m: zeromatrix(2,2);

m: minor(m,2,2);

matrixp(m);

Calculate

? matrixp;

Calculate

m:[[1,2],[3,4]];

matrixp(m);

Calculate

##### matrixp-minor

m: zeromatrix(2,2);

m: minor(m,2,2);

matrixp(m);

Calculate

? matrixp;

Calculate

### matrixp

Run Example
```(%i1)? matrixp;

-- Function: matrixp (<expr>)
Returns `true' if <expr> is a matrix, otherwise `false'.

There are also some inexact matches for `matrixp'.
Try `?? matrixp' to see them.

(%o1)                                true
(%i2) ```
Run Example
```m: matrix();
(%o1)                              matrix()
(%i2) matrixp(m);
(%o2)                                true
(%i3) m: matrix([]);
(%o3)                             matrix([])
(%i4) matrixp(m);
(%o4)                                true
(%i5) m:matrix([1,2,3],[3,4,5]);
[ 1  2  3 ]
(%o5)                             [         ]
[ 3  4  5 ]
(%i6) matrixp(m);
(%o6)                                true
(%i7) op(m);
(%o7)                               matrix
(%i8) length(m);
(%o8)                                  2
(%i9) part(m,1);
(%o9)                              [1, 2, 3]
(%i10) part(m,2);
(%o10)                             [3, 4, 5]
(%i11) col(m,1);
[ 1 ]
(%o11)                               [   ]
[ 3 ]
(%i12) ```
Run Example
```m:matrix([[1,2,3],[4,5,6],[7,8,9]]);
(%o1)                 [ [1, 2, 3]  [4, 5, 6]  [7, 8, 9] ]
(%i2) matrixp(m);
(%o2)                                true
(%i3) m[1];
(%o3)                  [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
(%i4) m[1][1][1];
(%o4)                                  1
(%i5) ```

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