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python dictionary list, getting an item inside a bracket [closed]

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items = {
'flour': [20, 10, 15, 8, 32, 15],
'beef': [3,4,2,8,2,4],
'bread': [2, 3, 3],
'cc': [0.3, 0.5, 0.8, 0.3, 1]
}
I ned to get the third element on each of the ingredients' bracket,
the answer will be (15, 2, 3, 0.8)
Please, thanks for your help!

You can do :
op = [v[2] for v in items.values()]
print(op)
Note: It won't maintain the same order in prior versions of python3.7

First number in list a variable isn't larger than [closed]

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Is there a quick way that doesn't involve a bunch of if-statements to get the first element in a list that my variable isn't bigger than? For example, if
x = 50
compare = [1, 4, 9, 16, 25, 36, 49, 64, 81]
I want this to return 64. My list will also be written in increasing order, so not every element in the list will need to be compared.

There's a short way of doing this that doesn't involve any for loop:
>>> x = 50
>>> compare = [1, 4, 9, 16, 25, 36, 49, 64, 81]
>>> next(item for item in compare if item >=x)
64
This creates an iterator of values that are >= x, and then selects the first one.

Use a loop. Test each element, and break out of the loop when you find what you're looking for.
result = None
for el in compare:
if x < el:
result = el
break
if result is not None:
print('Found', result)
else:
print('Not found')

Here is a solution with numpy:
import numpy as np
x = 50
compare = np.array([1, 4, 9, 16, 25, 36, 49, 64, 81] )
compare[compare>=x][0]

I would use a while loop:
count = 0
while x < compare[count]:
count += 1
print(compare[count])

python: how can i create a list of integers,to a number? [closed]

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I receive an input int that I don't previously know. How can I create a new list of integer from 0 to that int? An easy way please. Thank you in advance.
I mean that:
k = n
...
list = [0, ... , k]

numbers = list(range(k+1)) # For Python 2, it is just range(k+1).
Given an integer k, which you can get with input.
The range creates an iterator (in Python 3) with those numbers (k+1 because it is not inclusive, but you need it to be), then we make it into a list.
Demo:
>>> k = int(input())
16
>>> numbers = list(range(k+1))
>>> numbers
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16]

A simple function would look like this, assuming you've got your input number n:
For python2.x:
def get_range(n):
return range(n + 1)
For python3.x:
def get_range(n):
return list(range(n + 1))
In either case:
int_list = get_range(10)
>>> print(int_list)
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

What is a clearer way to generate this sequence of numbers? [closed]

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I have to generate a list like this:
[0, 2, 6, 12, 20, 30, 42, 56, 72, 90]
and this is my current code
g = lambda x: x + g(x - 2) if x > 0 else 0
print([g(2 * i) for i in range(10)])
Is there a clearer and more direct way to generate the sequence?

These appear to be the first few pronic numbers. That is, a number which is the product of two consecutive integers, n * (n + 1).
I've found this by searching in the OEIS. It's simple to generate them with a list comprehension:
>>> [x*(x + 1) for x in range(10)]
[0, 2, 6, 12, 20, 30, 42, 56, 72, 90]

Your algorithm is, as #wim has already pointed out, for "pronic numbers", and can be summarised to:
The n-th pronic number is the sum of the first n even integers
You can therefore write it as:
def pronic(n):
"""Create a list of the first n pronic numbers."""
return [sum(range(0, 2*i+1, 2)) for i in range(n)]
However, while this is a clear implementation of the approach you've taken, the other definition can make it even neater, as #wim's answer shows.
You could also consider implementation as a generator:
def pronic():
"""Generate the pronic numbers."""
i = 0
while True:
yield i * (i + 1)
i += 1

list1 = [x+(x ** 2) for x in range(10)]
print list1
Output : [0, 2, 6, 12, 20, 30, 42, 56, 72, 90]
This will give you the series that you have asked for.

Get numerical values from string input in Python [closed]

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I need to make a function that takes a string as input and outputs a list of all numerical values.
Some examples:
"22-28, 31-35, 37" should output: [22, 23, 24, 25, 26, 27, 28, 31, 32, 33, 34, 35, 37]
"22, 24" should output: [22, 24]
"23" should output: [23]
How can I do this?

Try regular expressions.
import re
r = re.findall('[0-9]+-[0-9]+|[0-9]+',string)
ans = []
for i in r:
if '-' in i:
t = i.split('-')
ans.extend(range(int(t[0]),int(t[1])))
else:
ans.append(int(i))
print ans

Without regular expressions:
def text_range(s):
res = []
for pc in s.split(','):
if '-' in pc: # this assumes no negative numbers in the list!
a,b = [int(i) for i in pc.split('-')]
res.extend(range(a, b+1))
else:
res.append(int(pc))
return res
then
text_range("22-28, 31-35, 37") # -> [22, 23, 24, 25, 26, 27, 28, 31, 32, 33, 34, 35, 37]