How to convert a string to a floating-point number in Python?

You can convert a string to a floating point number using the built-in `float()` function in Python. The syntax of this function is as follows:

float(string)

In this case, `string` is the string that needs to be converted to a floating point number.

Here is a detailed example demonstrating how to convert a string to a float:

# 定义一个字符串
string_number = "3.14"
# 使用float()函数将字符串转换为浮点数
float_number = float(string_number)
# 打印结果
print(float_number)  # 输出：3.14

In the example above, we first defined a string variable `string_number` containing the string “3.14” which represents a floating point number. Then, we used the `float()` function to convert this string into a floating point number and assigned the result to the variable `float_number`. Finally, we printed the value of `float_number`, displaying the converted floating point number 3.14.

It is important to note that if the string being converted cannot be parsed as a valid float, for example if it contains non-numeric characters or multiple decimal points, the `float()` function will raise a `ValueError` exception. Therefore, it is crucial to ensure that the string meets the formatting requirements for a float when converting from a string to a float.