Python根据字典值降序的第一个元素打印字典

Question

I have a dict likes this:

mydict =  {
'Peter': [21, 2, 42.0], 
'Kate': [15, 3, 45.0],
'Tom': [16, 6, 96.0],
'Lucy': [28, 4, 112.0],
 }

The key is string,value is list. I want to print mydict according to the first element in the dictionary value descending order.

For example, I want this output：

 'Lucy',28,4,112.0
 'Peter',21,2,42.0
 'Tom',16,6,96.0
 'Kate',15,3,45.0

How can I output such a result？

Answer 1

You can iterate over the sorted result of dict.items , and use str.join :

mydict = {
'Lucy': [28, 4, 112.0], 
'Peter': [21, 2, 42.0], 
'Kate': [15, 3, 45.0], 
'Tom': [16, 6, 96.0]}
for a, b in sorted(mydict.items(), key=lambda x:x[-1][0] if isinstance(x, list) else x, reverse = True):
  print('{},{}'.format(a, ','.join(map(str, b)) if isinstance(b, list) else b))

Output:

Lucy,28,4,112.0
Peter,21,2,42.0
Tom,16,6,96.0
Kate,15,3,45.0