How do I convert a string to a floating-point number in Python?
Gable E

In Python, you can convert a string to a floating-point number using thefloat() function or theast.literal_eval() function from theast module. Here's a detailed explanation of both approaches: Using the float() function: Thefloat() function is a built-in function in Python that converts a string to a floating-point number.

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string_number = "3.14"

float_number = float(string_number)

print(float_number)  # Output: 3.14

In this example,float_number = float(string_number) converts the string"3.14" to a floating-point number using thefloat() function. The resulting floating-point number is assigned to the variablefloat_number. It's important to note that if the string cannot be converted to a valid floating-point number, aValueError will be raised. For example, if the string contains non-numeric characters or an invalid format, such as multiple decimal points, the conversion will fail. Using the ast.literal_eval() function: Theast.literal_eval() function from theast module can be used to safely evaluate and convert a string representation of a number to its corresponding numeric value, including floating-point numbers.

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import ast

string_number = "3.14"

float_number = ast.literal_eval(string_number)

print(float_number)  # Output: 3.14

In this example,float_number = ast.literal_eval(string_number) usesast.literal_eval() to safely evaluate the string"3.14" and convert it to a floating-point number. The resulting floating-point number is assigned to the variablefloat_number. Unlike thefloat() function,ast.literal_eval() can handle more complex expressions and evaluate them safely. However, it should be used with caution as it can evaluate any valid Python expression, not just numeric values. Both approaches allow you to convert a string to a floating-point number in Python. Thefloat() function provides a simple and straightforward method, whileast.literal_eval() offers a more robust and secure approach for handling more complex expressions. Choose the method that best fits your specific requirements and input data.

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