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Title: Put similar‘123.456‘string into floating-point data

• Method One:

    print ‘{:.3f}‘.format(float(‘123.456‘))  >>> 123.456

• Method Two: Specifying map , reduce higher order functions

  Idea: The decimal point is processed first, and then the integer digits and decimal places are added. Steps are as follows

  s = ‘123.456‘

2. Working with decimals: Use a string slice method.

   s.split(‘.‘)

   This gives you 2 an array of length[‘123‘, ‘456‘]

4. Processes the first element in the list (an integer column). Use an iterative approach to get integers123

   def map_int(s):     ‘‘‘ @see: 迭代时把字符串转换成int类型 ‘‘‘ return int(s)

   Then use the higher map(func, seq) -order function to iterate over the string in the list: get[1, 2, 3]

    map(map_int, s.split(‘.‘)[0])

6. Uses higher-order functions Reduce (func, seq) to accumulate data after map () 123

    Reduce (lambda x, y: x*10 + y, map (map_int, S.split ('. ') [0]))  

   " > reduce (lambda x,y:x*10 + y, map (Map_int, S.split (". [0]))

   The same method handles decimal digits

    Reduce (lambda x, y: x*0.1 + y, map (map_int, S.split ('. ') [1] [::-1])) * 0.1  

   "> reduce (lambda x,y:x*0.1 + y, map (Map_int, S.split ( ") [1][::-< span class= "Hljs-number" >1])) * 0.1

• The entire code block is as follows: or simply replace the Map_int () function with the following: Lambda X:int (x)

    def Map_int(s): "@see: Convert a string to int type ' return int (s) reduce (lambda x,y:x*+ y) at iteration Map (Map_int, S.split ('. ') [0]) + reduce (lambda x,y:x*0.1 + y, map (Map_int, S.split ('. ') [1][::-1]) * 0.1              

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A python question previously asked by a colleague