# Python float() Function – Tutorial with Examples

The `float()` function in Python is a built-in function that is used to convert a number or a string to a floating-point number. It is used to convert an object to a floating-point number. If the argument passed to the function is a string, it must contain a valid number representation. If the argument is not a string or a number, the function raises a `TypeError` exception.

## Syntax

```float(x)
```

## Parameters

• `x` – The number or string to be converted to a floating-point number

## Return Value

The `float()` function returns a floating-point number representation of the argument passed to it.

## Examples

### Example 1: Converting a Number to a Floating-Point Number

```number = 10
result = float(number)
print(result)
```

Output:

```10.0
```

In this example, the variable `number` is assigned the value 10. The `float()` function is then used to convert this number to a floating-point number, and the result is stored in the variable `result`. The value of `result` is then printed, and it is a floating-point number representation of the original number.

### Example 2: Converting a String to a Floating-Point Number

```string = "10.5"
result = float(string)
print(result)
```

Output:

```10.5
```

In this example, the variable `string` is assigned a string representation of a floating-point number. The `float()` function is then used to convert this string to a floating-point number, and the result is stored in the variable `result`. The value of `result` is then printed, and it is a floating-point number representation of the original string.

### Example 3: Converting an Object to a Floating-Point Number

```class MyNumber:
def __init__(self, value):
self.value = value
def float(self):
return float(self.value)

my_number = MyNumber(10)
result = float(my_number)
print(result)
```

Output:

```10.0
```

In this example, a custom class `MyNumber` is defined, which has a `__float__()` method. This method is used to convert the value stored in an instance of the class to a floating-point number. An instance of the class `MyNumber` is created with the value 10, and this instance is passed to the `float()` function. The `float()` function then calls the `float()` method of the class to convert the value to a floating-point number, and the result is stored in the variable `result`. The value of `result` is then printed, and it is a floating-point number representation of the original value stored in the instance of the class.

## Use Cases

The `float()` function has various use cases in Python programming, some of which are:

• Converting a number to a floating-point number
• Converting a string representation of a number to a floating-point number
• Converting an object to a floating-point number

The `float()` function is commonly used when working with mathematical operations in Python, as many mathematical operations require floating-point numbers as input.