# numpy.eye() in Python

numpy.eye(R, C = None, k = 0, dtype = type <‘float’>) : –The eye tool returns a 2-D array with  1’s as the diagonal and  0’s elsewhere. The diagonal can be main, upper, or lower depending on the optional parameter k. A positive k is for the upper diagonal, a negative k is for the lower, and a  0 k (default) is for the main diagonal.

Parameters :

```R : Number of rows
C : [optional] Number of columns; By default M = N
k : [int, optional, 0 by default]
Diagonal we require; k>0 means diagonal above main diagonal or vice versa.
dtype : [optional, float(by Default)] Data type of returned array.
```

Returns :

```array of shape, R x C, an array where all elements
are equal to zero, except for the k-th diagonal,
whose values are equal to one.
```

Example:

## Python

 `# Python Programming illustrating` `# numpy.eye method`   `import` `numpy as geek`   `# 2x2 matrix with 1's on main diagnol` `b ``=` `geek.eye(``2``, dtype ``=` `float``)` `print``(``"Matrix b : \n"``, b)`   `# matrix with R=4 C=5 and 1 on diagnol` `# below main diagnol` `a ``=` `geek.eye(``4``, ``5``, k ``=` `-``1``)` `print``(``"\nMatrix a : \n"``, a)`

Output :

```Matrix b :
[[ 1.  0.]
[ 0.  1.]]

Matrix a :
[[ 0.  0.  0.  0.  0.]
[ 1.  0.  0.  0.  0.]
[ 0.  1.  0.  0.  0.]
[ 0.  0.  1.  0.  0.]]
```

Note :
These codes won’t run on online-ID. Please run them on your systems to explore the working.
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