float() to convert string to floating point number in Python

float() returns floating point number by taking string or integer as input .

Here are some examples with different type of input numbers

print(float())       # 0.0 
print(float(5))      # 5.0
print(float("34.5")) # 34.5

String inputs

print(float("  45.8 ")) # 45.8
print(float("InF"))     # inf
print(float("NaN"))     #nan
print(float("Infinity"))#inf

We will get error message based on input

print(float('abc45'))

Output

ValueError: could not convert string to float: 'abc45'

Data type

We can check type of data by using type(). Here we have used one float number.

print(type(4.5)) # <class 'float'>

Handling Conversion Errors

Use try-except to handle cases where the input is not a valid float:

try:
    print(float('abc'))
except ValueError:
    print("Invalid input for float conversion")

Use Case: Parsing User Input

In web forms or data input systems, user input is often received as a string. You can use float() to safely convert this data into a usable floating-point number:

user_input = "45.67"
converted_value = float(user_input)
print(converted_value)  # Output: 45.67

Special Values

The float() function can handle special values like inf and NaN:

print(float('NaN'))   # Output: nan
print(float('Inf'))   # Output: inf

bin() int() complex()

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Subhendu Mohapatra

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