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How to convert CSV data into a dictionary using itertools.groupby

I have a text file, job.txt, which is below
job,salary
Developer,29000
Developer,28000
Tester,27000
Tester,26000
My code is
with open(r'C:\Users\job.txt') as f:
file_content = f.readlines()
data = {}
for i, line in enumerate(file_content):
if i == 0:
continue
job, salary = line.split(",")
job = job.strip()
salary = int(salary.strip())
if not job in data:
data[job] = []
data[job].append(salary)
print("data =", data)
My expected result is below
data = {'Developer': [29000, 28000], 'Tester': [27000, 26000]}
How can I convert my code to use itertools.groupby?

Here is the code that will generate the dictionary you wanted.
from itertools import groupby
data = [
["Developer",29000],
["Developer",28000],
["Tester",27000],
["Tester",26000]
]
def keyfunc(e):
return e[0]
unique_keys = {}
data = sorted(data, key=keyfunc)
for k, g in groupby(data, keyfunc):
unique_keys[k] = [i[1] for i in g]
>>> print(unique_keys)
{'Developer': [29000, 28000], 'Tester': [27000, 26000]}
P.S: I would suggest using the csv module to read the file instead of doing it yourself.

Try this if pandas is an option:
from collections import defaultdict
import pandas as pd
d = pd.read_csv('job.txt').to_numpy().tolist()
res = defaultdict(list)
for v, k in d: res[v].append(k)
d = dict(res)
d
# {'Developer': [29000, 28000], 'Tester': [27000, 26000]}

You can only rely on groupby if your data is already chunked into categories.
from itertools import groupby
with open("job.txt") as f:
rows = [x.split(",") for x in f.readlines()[1:]]
data = {
k.strip(): [int(y[1]) for y in v]
for k, v in groupby(rows, key=lambda x: x[0])
}
With that in mind, I think a defaultdict is more appropriate here. Ordering is automatically handled and it's just less clever. Additionally, there's no need to slurp the file into memory or sort it (if unordered). Use dict(data) at the end if you don't like the defaultdict subclass.
from collections import defaultdict
data = defaultdict(list)
with open("job.txt") as f:
for i, line in enumerate(f):
if i:
job, salary = [x.strip() for x in line.split(",")]
data[job].append(int(salary))
As mentioned in the accepted answer, do prefer a CSV module if your actual data is at all more complicated than your example. CSVs can be difficult to parse and there's no reason to reinvent the wheel.

Print out dictionary from file

E;Z;X;Y
I tried
dl= defaultdict(list)
for line in file:
line = line.strip().split(';')
for x in line:
dl[line[0]].append(line[1:4])
dl=dict(dl)
print (votep)
It print out too many results. I have an init that reads the file.
What ways can I edit to make it work?

The csv module could be really handy here, just use a semicolon as your delimiter and a simple dict comprehension will suffice:
with open('filename.txt') as file:
reader = csv.reader(file, delimiter=';')
votep = {k: vals for k, *vals in reader}
print(votep)
Without using csv you can just use str.split:
with open('filename.txt') as file:
votep = {k: vals for k, *vals in (s.split(';') for s in file)}
print(votep)
Further simplified without the comprehension this would look as follows:
votep = {}
for line in file:
key, *vals = line.split(';')
votep[key] = vals
And FYI, key, *vals = line.strip(';') is just multiple variable assignment coupled with iterable unpacking. The star just means put whatever’s left in the iterable into vals after assigning the first value to key.

if you read file in list object, there is a simple function to iterate over and convert it to dictionary you expect:
a = [
'A;X;Y;Z',
'B;Y;Z;X',
'C;Y;Z;X',
'D;Z;X;Y',
'E;Z;X;Y',
]
def vp(a):
dl = {}
for i in a:
split_keys = i.split(';')
dl[split_keys[0]] = split_keys[1:]
print(dl)

Making python dictionary from a text file with multiple keys

I have a text file named file.txt with some numbers like the following :
1 79 8.106E-08 2.052E-08 3.837E-08
1 80 -4.766E-09 9.003E-08 4.812E-07
1 90 4.914E-08 1.563E-07 5.193E-07
2 2 9.254E-07 5.166E-06 9.723E-06
2 3 1.366E-06 -5.184E-06 7.580E-06
2 4 2.966E-06 5.979E-07 9.702E-08
2 5 5.254E-07 0.166E-02 9.723E-06
3 23 1.366E-06 -5.184E-03 7.580E-06
3 24 3.244E-03 5.239E-04 9.002E-08
I want to build a python dictionary, where the first number in each row is the key, the second number is always ignored, and the last three numbers are put as values. But in a dictionary, a key can not be repeated, so when I write my code (attached at the end of the question), what I get is
'1' : [ '90' '4.914E-08' '1.563E-07' '5.193E-07' ]
'2' : [ '5' '5.254E-07' '0.166E-02' '9.723E-06' ]
'3' : [ '24' '3.244E-03' '5.239E-04' '9.002E-08' ]
All the other numbers are removed, and only the last row is kept as the values. What I need is to have all the numbers against a key, say 1, to be appended in the dictionary. For example, what I need is :
'1' : ['8.106E-08' '2.052E-08' '3.837E-08' '-4.766E-09' '9.003E-08' '4.812E-07' '4.914E-08' '1.563E-07' '5.193E-07']
Is it possible to do it elegantly in python? The code I have right now is the following :
diction = {}
with open("file.txt") as f:
for line in f:
pa = line.split()
diction[pa[0]] = pa[1:]
with open('file.txt') as f:
diction = {pa[0]: pa[1:] for pa in map(str.split, f)}

You can use a defaultdict.
from collections import defaultdict
data = defaultdict(list)
with open("file.txt", "r") as f:
for line in f:
line = line.split()
data[line[0]].extend(line[2:])

Try this:
from collections import defaultdict
diction = defaultdict(list)
with open("file.txt") as f:
for line in f:
key, _, *values = line.strip().split()
diction[key].extend(values)
print(diction)
This is a solution for Python 3, because the statement a, *b = tuple1 is invalid in Python 2. Look at the solution of #cha0site if you are using Python 2.

Make the value of each key in diction be a list and extend that list with each iteration. With your code as it is written now when you say diction[pa[0]] = pa[1:] you're overwriting the value in diction[pa[0]] each time the key appears, which describes the behavior you're seeing.
with open("file.txt") as f:
for line in f:
pa = line.split()
try:
diction[pa[0]].extend(pa[1:])
except KeyError:
diction[pa[0]] = pa[1:]
In this code each value of diction will be a list. In each iteration if the key exists that list will be extended with new values from pa giving you a list of all the values for each key.

To do this in a very simple for loop:
with open('file.txt') as f:
return_dict = {}
for item_list in map(str.split, f):
if item_list[0] not in return_dict:
return_dict[item_list[0]] = []
return_dict[item_list[0]].extend(item_list[1:])
return return_dict
Or, if you wanted to use defaultdict in a one liner-ish:
from collections import defaultdict
with open('file.txt') as f:
return_dict = defaultdict(list)
[return_dict[item_list[0]].extend(item_list[1:]) for item_list in map(str.split, f)]
return return_dict

Converting text file to dictionary in python

So lets say I want to convert the following to a dictionary where the 1st column is keys, and 2nd column is values.
http://pastebin.com/29bXkYhd
The following code works for this (assume romEdges.txt is the name of the file):
f = open('romEdges.txt')
dic = {}
for l in f:
k, v = l.split()
if k in dic:
dic[k].extend(v)
else:
dic[k] = [v]
f.close()
OK
But why doesn't the code work for this file?
http://pastebin.com/Za0McsAM
If anyone can tell me the correct code for the 2nd text file to work as well I would appreciate it.
Thanks in advance.

You should use append instead of extend
from collections import defaultdict
d = defaultdict(list)
with open("romEdges.txt") as fin:
for line in fin:
k, v = line.strip().split()
d[k].append(v)
print d
or using sets to prevent duplicates
d = defaultdict(set)
with open("romEdges.txt") as fin:
for line in fin:
k, v = line.strip().split()
d[k].add(v)
print d

If you want to append the data to dictionary, then you can use update in python. Please use following code:
f = open('your file name')
dic = {}
for l in f:
k,v = l.split()
if k in dic:
dict.update({k:v })
else:
dic[k] = [v]
print dic
f.close()
output:
{'0100464': ['0100360'], '0100317': ['0100039'], '0100405': ['0100181'], '0100545': ['0100212'], '0100008': ['0000459'], '0100073': ['0100072'], '0100044': ['0100426'], '0100062': ['0100033'], '0100061': ['0000461'], '0100066': ['0100067'], '0100067': ['0100164'], '0100064': ['0100353'], '0100080': ['0100468'], '0100566': ['0100356'], '0100048': ['0100066'], '0100005': ['0100448'], '0100007': ['0100008'], '0100318': ['0100319'], '0100045': ['0100046'], '0100238': ['0100150'], '0100040': ['0100244'], '0100024': ['0100394'], '0100025': ['0100026'], '0100022': ['0100419'], '0100009': ['0100010'], '0100020': ['0100021'], '0100313': ['0100350'], '0100297': ['0100381'], '0100490': ['0100484'], '0100049': ['0100336'], '0100075': ['0100076'], '0100074': ['0100075'], '0100077': ['0000195'], '0100071': ['0100072'], '0100265': ['0000202'], '0100266': ['0000201'], '0100035': ['0100226'], '0100079': ['0100348'], '0100050': ['0100058'], '0100017': ['0100369'], '0100030': ['0100465'], '0100033': ['0100322'], '0100058': ['0100056'], '0100013': ['0100326'], '0100036': ['0100463'], '0100321': ['0100320'], '0100323': ['0100503'], '0100003': ['0100004'], '0100056': ['0100489'], '0100055': ['0100033'], '0100053': ['0100495'], '0100286': ['0100461'], '0100285': ['0100196'], '0100482': ['0100483']}

Python: Data Getting

Im trying to find out how to get certain data from a file in the easiest way possible. I have searched all over the internet but can't find anything. I want to be able to do this:
File.txt:
data1 = 1
data2 = 2
but i want to get only data1 like so,
p = open('file.txt')
f = p.get(data1)
print(f)
Any Ideas, Thanks in advance.

You can do:
with open("file.txt", "r") as f:
for line in f:
key, val = line.split('=')
key = key.strip()
val = val.strip()
if key == 'data1': # if data1 is not the first line
# do something with value and data
using map:
from operator import methodcaller
with open("file.txt", "r") as f:
for line in f:
key, val = map(methodcaller("strip", " "), line.split('='))
if key == "data1":
# do something with value and data

with open("file.txt", "r") as f:
key, val = f.readline().split('=')
if key.strip() == 'data1': # if data1 is not the first line
# do something with value and data

If you know you only want data1 which is on the first line, you can do
with open('file.txt', 'r') as f:
key, val = tuple(x.strip() for x in f.readline().split('='))
The list comprehension is used to remove the whitespace from each string.