Python: Build a dictionary from a file's contents
Say that I have a file of names and values with entries like this:
lasker:22,45,77,101
kramnik:45,22,15,105
What开发者_如何转开发's the most Pythonic way to get them into a dictionary with the name as the key and the values as a list like this:
{ 'lasker': (22,45,77,101), 'kramnik': (45,22,15,105) }
EDIT
And is there anyway to iterate through them in the order I read them from the file or would this require a different data structure?
I think it is pretty clear how this code works:
def get_entries( infile ):
with open( infile, 'rt') as file:
for line in file:
name, nums = line.split(':', 1)
yield name, tuple(int(x) for x in nums.split(','))
# dict takes a sequence of `(key, value)` pairs and turns in into a dict
print dict(get_entries( infile ))
Writing a generator that yields pairs and passing it to dict
is a extremely useful pattern.
If you just want to iterate over the pairs you can do this directly:
for name, nums in get_entries( infile ):
print name, nums
but if you need dict access later but also ordering you can simply replace the dict
with a OrderedDict
:
from collections import OrderedDict
print OrderedDict(get_entries( infile ))
No need to care about lines with a regex:
import re
pat = re.compile('([a-z]+)\s*:\s*(\d+(?:\s*,\s*\d+)*)')
with open('rara.txt') as f:
dic = dict((ma.group(1),map(int,ma.group(2).split(','))) for ma in pat.finditer(f.read()))
print dic
Tested with following text in 'rara.txt' file's text:
lasker : 22,45, 77,101 kramnik:888 ,22,15,105 kramniu :45,22, 3433,105 6765433 laskooo:22,45, 77 , 101 kooni:
45, 78 45kramndde:45,334 ,15,105 tasku: 22,45 ,7,101 krammma: 1105oberon glomo:22, 3478,77 ,101 draumnik:45,105
toyku:22,45,7,101 solo
ytrmmma:1105oberon radabidadada lftyker:22,3478,7,101
Result
{'laskooo': [22, 45, 77, 101], 'tasku': [22, 45, 7, 101], 'krammma': [1105], 'glomo': [22, 3478, 77, 101], 'kramniu': [45, 22, 3433, 105], 'kooni': [45, 78], 'lftyker': [22, 3478, 7, 101], 'toyku': [22, 45, 7, 101], 'kramnik': [888, 22, 15, 105], 'draumnik': [45, 105], 'ytrmmma': [1105], 'lasker': [22, 45, 77, 101], 'kramndde': [45, 334, 15, 105]}
EDIT: I modified the regex pattern (added \s* ) and the 'rara.txt' file's text
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