In this post, we are going to learn **How to set variables to Nan in Python**. The Nan is not a number that is used to represent the missing or undefined values. It is particularly floating-point values. The **Nan **is also set to variables that do not have values that have yet not computed.

## How to set variable to Nan in Python

The python built-in float() function is used to assign Nan values to a variable. We have to just pass the string **“Nan”** as a parameter to the float function. The **“Nan”** is case insensitive so we can use the following format to assign to a variable. Let us understand with the below examples

```
float("nan")
float("+nan")
float("-nan")
float("nAn")
float("nAN")
float("naN")
float("Nan")
float("NAn")
float("NAN")
float("NaN")
```

```
negInf = float('nan')
print('The Value you have assigned is:',negInf)
```

Output

```
The Value you have assigned is : nan
```

### 2. How to Set a variable Nan in Python using decimal

In this python program, We have used a decimal module to assign a variable to **nan **values in python. First, we have to import the decimal module and used **Decimal(“Nan”)** to assign variables to the nan value.

```
from decimal import Decimal
nanval = Decimal("Nan")
print ('Value you have assigned is :',nanval )
```

Output

```
Value you have assigned is : NaN
```

### 3.. How to Set a variable Nan Python using decimal

The python math module attribute is also a great choice to set a variable to nan. First, we’ll import the math module and assign the variable to nan using “math. **nan”**

```
import math
nanval = math.nan
print ('Value you have assigned :',nanval )
```

Output

```
Value you have assigned is : NaN
```

### 4. Set a variable Nan Python using numpy

The python numpy module can also be used to assign a variable to nan in Python. First, we have to install the numpy library if not already installed on our system and Import it to our program by using **“import numpy as np”** the numpy library attribute np.nan is used to assign a variable to **nan**.

```
import numpy as np
nanval = np.nan
print ('Value is nan:',np.isnan(nanval) )
print ('Value you have assigned :',nanval )
```

Output

```
Value is nan: True
Value you have assigned : nan
```

### Summary

In this post, we have learned how To Set Variable To Nan In Python by using the 4 different ways with the help of modules **numpy, math, decimal, **and python built-in float function.