How to Use the Python float() Function
In this tutorial, you'll learn how to use the float() function in Python. The float() function converts a number or string representing a number to a floating-point number.
Python float() Function Syntax
The syntax of the float() function is as follows:
float(value)
The float() Function Parameter
- value: A number or string representing a number
Remarks
- float() return 0.0 if no parameter is given.
- If the value is a string, it can contain leading and trailing white spaces.
Examples
Convert a String to a Floating-Point Number
The following sample code illustrates an example of converting a string representing a number to a floating-point number:
value = "120.534"
number = float(value)
print (number)
Output:
120.534
Convert a Numeric Number to a floating-point Number
The following code converts a numeric number to a floating-point number:
value = 124.9293
number = float(value)
print (number)
Output:
124.9293
Convert a String Representing a Negative Numeric Number
Example:
value = "-1e-003"
number = float(value)
print (number)
Output:
-0.001
Convert a String Representing a Positive Numeric Number
Example:
value = '+1E6'
number = float(value)
print (number)
Output:
1000000.0
Convert a String Containing Leading and Trailing Spaces
Sample code that converts a string containing leading and leading spaces to a floating-point number:
value = ' +1E6 '
number = float(value)
print (number)
Output:
+1000000.0
Convert a String Not Representing a Number
Sample code that converts a string not representing a number to a floating number:
value = ' NaN '
number = float(value)
print (number)
Output:
nan
Convert a String Representing Infinity
Example:
value = ' -INFINITY '
number = float(value)
print (number)
Output:
-inf
The float() Function without Argument
The following is an example of using float() with no argument:
number = float()
print (number)
Output:
0.0
In this tutorial, you've learned how to use the Python float() function. The float() function is a function to convert a number or string representing a number to a floating-point number.