entry and the entry before the last [closed] - python

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Im new to python.i have absolutly no idea how to solve this:
Extends the list with a While loop or For loop, so that the next entry is the sum of the last entry and the previous entry:
myListe = [1,2,3]


Deducing from your given values, you are starting out from
myListe = [1, 2, 3]
# ^ ^
# index -3 -1
and are supposed to add the last element and the one two before that.
This, you can achieve via:
while True:
next_value = myListe[-3] + myListe[-1]
if next_value > 1000:
break
myListe.append(next_value)
You can verify that the last value in the list is then in deed 872.
myListe[-3:]
# [406, 595, 872]
Using some knowledge about built-in utils, slices and named assignments (Python >= 3.8), you can simplify the while loop:
while (next_value := sum(myListe[-3::2])) <= 1000:
myListe.append(next_value)

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With python; Getting index of wrong item of list [closed]

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I'm trying to get the indeces of the items of my list but on one item it returns a wrong index. There are two numbers who are the same in the list, maybe it confuses it with the first one.
The list is: [0,1,0,0,0,0,0,0,0,0,6,1,0]
for i in neu:
if (i > 0):
zahl = neu.index(i) + 7
print(zahl)
browser.find_element_by_xpath("//*[#id='tabelle_merkliste']/tbody/tr['zahl']/td[10]/img")
print("found")
"print(Zahl)" returns these sums:
8
17
8 (should be 18)
Maybe someone got an idea why this happens, thanks in advance.

Use enumerate:
for i, value in enumerate(neu):
if (value > 0):
zahl = i + 7
print(zahl)
browser.find_element_by_xpath("//*[#id='tabelle_merkliste']/tbody/tr['zahl']/td[10]/img")
print("found")

list comprehension - how to write previous number? [closed]

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How to select the previous number in list comprehension that starts from the second one?
The formula is [w(j-1)* 5 +w for t in y]?
w(j-1) is the first number in list.

Not exactly sure what you are trying to achieve. Therefore, my own interpretation of the problem. Assume you have a list of numbers:
my_list = range(1, 10)
Now we want to iterate over this list starting from the second entry and also access the previous entry:
new_list = [my_list[i - 1]*5 + my_list[i] for i, n in enumerate(my_list) if i > 0]
print(new_list)
This way you can get access to a list element and its predecessor.
Is this what you are trying to achieve?

python: list of tuples search [closed]

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Need some help here
num = [(1,4,5,30,33,41,52),(2,10,11,29,30,36,47),(3,15,25,37,38,58,59)]
if the last 6 digits are located to return the first digit.
example if finds 10,11,29,30,36,47 return 2

You can use next similair to user's approach:
num = [(1,4,5,30,33,41,52),(2,10,11,29,30,36,47),(3,15,25,37,38,58,59)]
to_find = [10,11,29,30,36,47]
print(next(n for n, *nums in num if nums == to_find))
2

You can use next with a conditional generator expression:
num = [(1,4,5,30,33,41,52),(2,10,11,29,30,36,47),(3,15,25,37,38,58,59)]
search = 11
next(first for first, *rest in num if search in rest)
# 2

Please explain the following inline python code? index = [n for n, value in enumerate(self.Variable[i]) if value == 1] [closed]

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I need to understand the following code.
The code is from a class method.
Code snippet
index = [n for n, value in enumerate(self.Variable[i]) if value == 1]

The above code can be rewritten as:
indices = []
for n, value in enumerate(self.BUSES[i]):
if value==1:
indices.append(n)
enumerate returns a pair of (index, value at that index) for a given list. So you are testing if value at a given index is 1, and if that is true, you add the index to indices.

Return an arbitary element from a set that satisfies a condition [closed]

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Is there a way to retrieve any arbitary element from a set that satisfies a particular condition?
For example, if my set has {1,2,3,4,5,6,7,8,9,10} .
Is there a way to retrieve any arbitary element that is less than 5?

You can pass random.choice a list that filters your set to the choices you want:
from random import choice
s = set([1,2,3,4,5,6,7,8,9,10])
choice([n for n in s if n < 5])
Of course, if you want all the items less than 5, it's just the list:
[n for n in s if n < 5]

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