Finding x numbers in list greater than 0 with potential duplicates and assigning index of original l-CodePudding

I have lists of floats which will have some zeros in it. Eg.

numbers = [1.2, 0.0, 0.0, 1.2, 2.0, 2.5, 17, 1.3, 1.8, 1.3, 1.2]

I am trying to assign these values to n numbers (assuming it will be the first 5) for the lowest 5 values that are greater than 0.

I can get the first by using:

first = min(o for o in numbers if o > 0)

But as there are duplicates in the smallest value (1.2), I cannot easily assign second, third, fourth and fifth.

I need to assign these and allow me to keep the index of their values in the original list and assign these too. Eg.

first_pos = numbers.index(first)

I cannot use the above for second as it will assign it the first index value.

Is there any efficient way using a for loop or list comprehension or even a small function to assigning the other numbers so that:

second = 1.2
second_pos = 4
third = 1.2
third_pos = 10
fourth = 1.3
fourth_pos = 7
fifth = 1.3
fifth_pos = 9

I cannot do this with any list comprehension I know of for second as it will not pick up a duplicate. Eg.:

sec = min(o for o in numbers if o > first)

The lists vary in length of values (at least 5, though) and may or may not have duplicates and zeros but many will.

CodePudding user response：

Ok, to badly answer my own question, I have been able to do this by copying and removing the zeros, enumerating over the list for the index values and removing each number once assigned:

number = [n for n in numbers if n > 0]
numbs = [n for n, x in enumerate(numbers) if x > 0]
for n in number:
  first = min(number)
  first_pos = number.index(first)
  first_ind = numbs[first_pos]
number.remove(first)
numbs.remove(first_ind)
for n in number:
  second = min(number)
  sec_pos = number.index(second)
  sec_ind = numbs[sec_pos]
number.remove(second)
numbs.remove(sec_ind)

This will keep and assign the values and indexes of each minimum value greater than zero.

Is there any way to add this into a function to assign all values greater than zero in the list to its own variables?

CodePudding user response：

IIUC, one way using sorted with enumerate:

sorted(((n, i) for n, i in enumerate(numbers) if i > 0), key=lambda x: x[1])[:5]

Output of (index, value) pairs of first 5 smallest values:

[(0, 1.2), (3, 1.2), (10, 1.2), (7, 1.3), (9, 1.3)]