Question

I want to find the highest and lowest values from a python list as mentioned below.

myList = [10,12,18,20,25,18,17,16,10,20,30,35,40,35,30,20,15]

我想找到。本清单(25)中的第一个最高值是(10)项中第一个最高数值之后的最低数值,随后是先前最低数值(40)之后的下一个最高数值,因此,在清单结束之前,其最低和最高数值及其各自的指数值。

因此,我所尝试的很多东西是一份清单中价值最高和价值最低的,但我希望在名单结束和各自的指数价值之前分别找到最低和最高数值。

Answer 1

您可尝试使用集体办法:

myList = [10,12,18,20,25,18,17,16,10,20,30,35,40,35,30,20,15]

from itertools import groupby

d = [ (myList[i],i) for _,(*_,i) in groupby(range(1,len(myList)),
                                    key=lambda i:myList[i-1]<myList[i]) ]

print(d)
[(25, 4), (10, 8), (40, 12), (15, 16)]

您还可以首先计算指数,并将数值分别计算:

myList = [10,12,18,20,25,18,17,16,10,20,30,35,40,35,30,20,15]

from itertools import groupby,accumulate

d         = (b>a for a,b in zip(myList,myList[1:]))
*indexes, = accumulate(len(g) for _,(*g,) in groupby(d)) 
values    = [myList[i] for i in indexes]

print(indexes)
print(values)

[4, 8, 12, 16]
[25, 10, 40, 15]

Answer 2

页: 1 in find find find

import itertools as it 

myList = [10,12,18,20,25,18,17,16,10,20,30,35,40,35,30,20,15]

for k,v in it.groupby(zip(myList, myList[1:]), lambda t: t[0]<t[1] ):
    print(list(v)[-1][-1])

印刷:

Answer 3

你们应当从清单中获取三个价值观并检查。

x1 < x2 > x3 to get local max
x1 > x2 < x3 to get local min

This is situation where you could use for-loop with range(len(...)) to work with index
to get three values myList[index-1], myList[index], myList[index+1] (instead of single value).

You should start at second item (index = 1) instead of first (index = 0)
because code uses index-1

And you should stop on len(myList)-1 instead of len(myList)
because code uses index+1

for i in range(1, len(myList)-1):
    print(myList[i-1], myList[i], myList[i+1])

and check

   is_max = (myList[i-1] < myList[i] > myList[i+1])
   is_min = (myList[i-1] > myList[i] < myList[i+1])

以后使用<代码>is_max和_is_min以显示或保持价值

    if is_max:
        # ... code ...
    elif is_min:
        # ... code ...
    else:
        # ... code ...

全面工作实例:

myList = [10,12,18,20,25,18,17,16,10,20,30,35,40,35,30,20,15]

for i in range(1, len(myList)-1):

    is_max = (myList[i-1] < myList[i] > myList[i+1])
    is_min = (myList[i-1] > myList[i] < myList[i+1])

    if is_max:
        print(f {i:3} | , myList[i-1], myList[i], myList[i+1],  max )
    elif is_min:
        print(f {i:3} | , myList[i-1], myList[i], myList[i+1],  min )
    else:
        print(f {i:3} | , myList[i-1], myList[i], myList[i+1])

结果:

  1 | 10 12 18
  2 | 12 18 20
  3 | 18 20 25
  4 | 20 25 18 max
  5 | 25 18 17
  6 | 18 17 16
  7 | 17 16 10
  8 | 16 10 20 min
  9 | 10 20 30
 10 | 20 30 35
 11 | 30 35 40
 12 | 35 40 35 max
 13 | 40 35 30
 14 | 35 30 20
 15 | 30 20 15

最后,您应使用<代码>>=,<=,而不是>,<。

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