How to Convert String to Float in Python?

Convert String to Float Value in Python

In Python, the default values that are fed by the user as the input are in string format, and many times we have to deal with the floating point, so we would have to explicitly convert the string values to float values. This can be done using several ways, such as by using the float function.

The conversion to float value can also be done using the NumPy, and the conversion can also be some specified format such as fixed decimal point conversion or converting the strings with a comma to floating-point values. Here we would see how we can convert the list of strings to float values. Several different methods which we would be learning several ways along with different examples to convert the string to float such as:-

1. Using float() function
2. Convert string having comma to a floating-point value
3. Convert the list of strings to float
4. Conversion to float value using the Numpy
5. Conversion to specified decimal point from string

Using float() Function

float() function is the most common way to convert the string to the float value. The float function takes the parameter y, which is a string, and would then convert the string to a float value and return its float value. While using the float function, we should keep in mind that the parameter y should have only the decimal value or the integer values, which can be converted to float value by the float function.

The value 0.0 is returned in the case when there is no argument provided to the function. Overflow error is given when the argument that is given as input cannot be contained by the floating-point data type.

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Convert a Number String with Commas into a Floating-point Object

If we have the string which contains a comma such as 1,2.56, we can not directly convert the string to float using the float() function as there the condition was that the parameter should only be in integer or decimal form, so we would have to firstly remove the comma and then use the flat function to convert the string value which contains the comma or decimal point to float value.

For removing the comma from the string, we would be replacing the comma with "" which would remove the comma from the string.

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Convert String to Float List in Python

If the string contains multiple float values, then we would have to, one by one, iterate over the value s in the string separated by a comma and then convert them to float values.

For example the string value be s=34.25, 36.24, 15.26, 47.51, 97.51 the the float list would contain the values [34.25, 36.24, 15.26, 47.51, 97.51]

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Convert a List of Strings to Float in Python

For converting the list of strings to a floating value list, we would have to iterate the string list and take the values one by one and then convert the string values to the floating values and then append all the float values to the floating value list.

For example the string list contains the value s=['34.25', '36.24', '15.26', '15.48', '15.30'] and the resulting float values would be [34.25, 36.24, 15.26, 15.48, 15.30]

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Convert String to Float Using Numpy

Numpy is a python library that allows users to execute high-level mathematical operations on massive, multi-dimensional arrays and matrices. The first step in using NumPy to convert a string to a float is to import the NumPy library, which would be used to convert the string to the float values. Later, you can convert the string to a floating-point value in Python using the astype method, which is an in-built technique.

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Convert String to Float with Specified Decimal Points

For converting the string to specified string to some specified decimal points, we would first be converting the values to the float values and then converting the float values to some specified decimal values. We would be using the format() function, which has the syntax {:.Nf}.format(float value) where Nf is the number of values that must be present after the decimal in the floating value.

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See Also:

• convert list to set in python
• convert list to tuple in python
• convert string to datetime in python
• convert list to string in python
• convert string to int in python