Python standard library: built-in functions float ([x]), pythonfloat

Python standard library: built-in functions float ([x]), pythonfloat

This function is used to convert a string or an integer to a floating point number. If the x parameter is a string, only a digit string in decimal format is used. You can add a symbol before the number to represent a positive or negative number. If the x parameter is an integer, it can be converted to a floating point. However, this function uses infinity or inf to represent the number of infinity. For example, if + inf is positive infinity,-inf is negative infinity. The concept of infinity is introduced here. What is the value of "infinity" multiplied by "0? Here is nan, that is, not a number (not a number ).

Example:

# Float () print (float ('37. 21 ') print (float (234) print (float (' + inf ') + 200000) print (float ('-inf ') * 0) print (float ('-12345 \ n') print (float ('1e-003 '))

The output result is as follows:

37.21

234.0

Inf

Nan

-12345.0

0.001

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