In a list of dictionaries, how can I find the minimum calue in a common dictionary field.

Question

[{'price': 99, 'barcode': '2342355'}, {'price': 88, 'barcode': '2345566'}]

I want to find out the minimum and maximum. I know I can sort this easily using a basic lambda function using the key,
but I know python must have a direct function to pull this off. can someone help me out?

Answer 1

There are several options. Here is a straight-forward one:

seq = [x['the_key'] for x in dict_list]
min(seq)
max(seq)
[Edit]

If you only wanted to iterate through the list once, you could try this

import sys

lo,hi = sys.maxint,-sys.maxint-1
for x in (item['the_key'] for item in dict_list):
    lo,hi = min(x,lo),max(x,hi)

Answer 2

If you only wanted to iterate through the list once, you could try this (assuming the values could be represented as ints):

import sys

lo,hi = sys.maxint,-sys.maxint-1
for x in (item['the_key'] for item in dict_list):
    lo,hi = min(x,lo),max(x,hi)