比较列表中的两个项目的问题

Question

I have this list

zipped_values = [(3.0, 4.242640687119285), (3.605551275463989, 3.1622776601683795), (5.0, 3.1622776601683795), (4.123105625617661, 4.47213595499958), (5.0, 4.0), (5.830951894845301, 7.810249675906654), (5.0990195135927845, 5.385164807134504), (7.0710678118654755, 8.06225774829855), (7.0710678118654755, 7.280109889280518), (8.06225774829855, 8.246211251235321)]

what I am trying to do is compare each item within the lists to each other (within the same list), to find out what the minimum is. In the first case, it would be 3.0, in the second, it would be 3.1.

Now what I am trying to do is, if the minimum is the first element, assign that element (3.0) to a dictionary key named M1, and if the minimum is the second element, assign that element to a dictionary key named M2.

This is what I've come up with:

  for jk in zipped_value:
    for n in jk:
      if zipped_value[0][n] < zipped_value[0][n+1]:
        dictionary["M1"].append(zipped_value[0][n])

But it gives me this error: TypeError: tuple indices must be integers or slices, not float

What do I do?

Answer 1

You don't need the inner loop. jk is the tuple, you just need to compare jk[0] with jk[1] . You can simplify this by unpacking to two variables when looping.

for a, b in zipped_values:
    if a < b:
        dictionary["M1"].append(a)
    else:
        dictionary["M2"].append(b)

Answer 2

Your inner for loop is iterating over the tuple, so the value of n is actually the float s in your tuple. Additionally, you will have problems with the append statement since it does not seem like you are initializing the dictionary values to be list type. Lastly, python allows you to unpack your tuples as you are iterative over them, making the code easier to read and comprehend rather than needing to use indices.

Try this:

from collections import defaultdict

dictionary = defaultdict(list)

for item1, item2 in zipped_value:
    if item1 < item2:
        dictionary["M1"].append(item1)
    else:
        dictionary["M2"].append(item2)

Answer 3

You are getting this error "TypeError: tuple indices must be integers or slices, not float" because in the "for n in jk" the 'n' here is actually representing the float values in tuples and is not the index of tuple. So,

if zipped_value[0][n] < zipped_value[0][n+1]:
    dictionary["M1"].append(zipped_value[0][n])

is not correct indexing to access elements of tuples in a list.

You can modify your code to something below to get correct results:

for jk in zipped_values:
  if jk[0] < jk[1]:
    dictionary["M1"].append(jk[0])
  else:
    dictionary["M2"].append(jk[1])