# numpy.isinf() in Python

numpy.isinf(array [, out]) : Test element-wise whether it is +ve or -ve infinity or not return the result as a boolean array.
Parameters :

```array : [array_like]Input array or object whose
elements, we need to test for  infinity
out   : [ndarray, optional]Output array placed
with result. Its type is preserved and
it  must be of the right shape to hold
the output.
```

Return :

```boolean array containing the result. For scalar
input, the result is a new boolean with value
True if the input is positive or negative infinity;
otherwise the value is False. For array input, the
result is a boolean array with the same shape as
the input and the values are True where the
corresponding element of the input is positive
or negative infinity; elsewhere the values are False.
```

Code 1 :

 `# Python Program illustrating ` `# numpy.isinf() method ` `  `  `import` `numpy as geek  ` ` `  `print``(``"Finite : "``, geek.isinf(``1``), ``"\n"``) ` ` `  `print``(``"Finite : "``, geek.isinf(``0``), ``"\n"``) ` ` `  `# not a number ` `print``(``"Finite : "``, geek.isinf(geek.nan), ``"\n"``) ` ` `  `#  infinity ` `print``(``"Finite : "``, geek.isinf(geek.inf), ``"\n"``) ` ` `  `print``(``"Finite : "``, geek.isinf(geek.NINF), ``"\n"``)  ` ` `  `x ``=` `geek.array([``-``geek.inf, ``0.``, geek.inf]) ` `y ``=` `geek.array([``2``, ``2``, ``2``]) ` `print``(``"Checking for infinity : "``, geek.isinf(x, y))  `

Output :

```Finite :  False

Finite :  False

Finite :  False

Finite :  True

Finite :  True

Checking for infinity :  [1 0 1]

```

Code 2 :

 `# Python Program illustrating ` `# numpy.isinf() method ` `   `  `import` `numpy as geek  ` `  `  `# Returns True/False value for each element  ` `b ``=` `geek.arange(``8``).reshape(``2``, ``4``) ` `                `  `print``(``"\n"``,b) ` `print``(``"\nIs Infifnity : \n"``, geek.isinf(b)) ` ` `  `# geek.inf  : Positive Infinity ` `# geek.NINF : negative Infinity ` `b ``=` `[[geek.inf],  ` `     ``[geek.NINF]] ` `print``(``"\nIs Infifnity : \n"``, geek.isinf(b)) `

Output :

```
[[0 1 2 3]
[4 5 6 7]]

Is Infifnity :
[[False False False False]
[False False False False]]

Is Infifnity :
[[ True]
[ True]]```

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