I want to write a function read_file() to read the values in the file and store the data in the a dictionary. The dictionary will look something like this:
product = {'d01':['pencil', 5], 'd02':['highlighter', 7], 'd03':['sharpener', 10]....}
What the items in the file looks like:
input:
d={}
file=r"C:\Users\Public\Documents\Folder\products.dat"
with open(file,'r') as f:
for items in f:
print(items)
results:
d01,pencil,5
d02,highlighter,7
d03,sharpener, 10
d04,pen,3
Here are my codes:
def read_file():
d={}
file=r"C:\Users\Public\Documents\Folder\products.dat"
with open(file,'r') as f:
for items in f:
stuff = items.split(",")
quantity = int(stuff[2].rstrip())
a = stuff[0]
b = [stuff[1], quantity]
d = {a:b}
print(d)
read_file()
Currently results I got:
{'d01': ['pencil', 5]}
{'d02': ['highlighter', 7]}
{'d03': ['sharpener', 10]}
{'d04': ['pen', 3]}
How do I achieve the above results?
Don't create a new dictionary for each line, add an element to the same dictonary.
Change
d = {a:b}
to
d[a] = b
And put print(d) after the loop is done, not inside the loop.
To read and parse a csv file into a dictionary of lists, using the first item on each line as a key and the remaining items on each line as a value list:
import csv
def parse(csvfilename):
dic = {}
with open(csvfilename, "r") as csvfile
csvreader = csv.reader(csvfile, skipinitialspace=True)
for row in csvreader:
table[row[0]] = row[1:]
return dic
Related
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)
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
I have this main function:
def main():
subprocess.call("cls", shell=True)
ipList,hostList,manfList,masterList,temp = [],[],[],[],[]
ipList,hostList,manfList, = getIPs(),getHosts(),getManfs()
entries = len(hostList)
i = 0
for i in xrange(i, entries):
temp = [[hostList[i]],[manfList[i]],[ipList[i]]]
masterList.append(temp)
with open("output.csv", "wb") as f:
writer = csv.writer(f, delimiter=',')
writer.writerows(masterList)
My current output is that it successfully writes to CSV but my objective is to remove the square brackets.
I tried using .join() method however I understand that it only takes single lists and not nested lists.
How can I achieve this given that I'm using a 3 dimensional list? Note, I intend to add more columns of data in the future.
Edit:
My current output for 1 row is similar to:
['Name1,'] ['Brand,'] ['1.1.1.1,']
I would like it to be:
Name1, Brand, 1.1.1.1,
Try to remove bracket for values in temp while creating masterList, because it will be nested list. So, the code should be:
def main():
subprocess.call("cls", shell=True)
ipList,hostList,manfList,masterList,temp = [],[],[],[],[]
ipList,hostList,manfList, = getIPs(),getHosts(),getManfs()
entries = len(hostList)
i = 0
for i in xrange(i, entries):
temp = [hostList[i], manfList[i], ipList[i]]
masterList.append(temp)
with open("output.csv", "wb") as f:
writer = csv.writer(f, delimiter=',')
writer.writerows(masterList)
What you could do is strip a string of the data maybe?
import string
writer.writerows(str(masterList).translate(string.maketrans('', ''), '[]\'')
E.g.
>>> import string
>>> temp = [['1.1.1'], ['Name1'], ['123']]
>>> str(temp).translate(string.maketrans('', ''), '[]\'')
'1.1.1, Name1, 123'
In Python 3.6:
>>> temp = [['1.1.1'], ['Name1'], ['123']]
>>> str(temp).translate({ord('['): '', ord(']'): '', ord('\''): ''})
'1.1.1, Name1, 123'
Try to change this:
temp = [[hostList[i]],[manfList[i]],[ipList[i]]]
to this:
temp = [hostList[i],manfList[i],ipList[i]]
I agree with the answers above, about the brackets removal, however if this is crucial to you for some reason, here is a function that takes a list as an input and returns you a csv row acceptable list.
def output_list(masterList):
output = []
for item in masterList:
if isinstance(item,list): #if item is a list
for i in output_list(item): #call this function on it and append its each value separately. If it has more lists in it this function will call itself again
output.append(i)
else:
output.append(item)
return output
You can use it in the line masterList.append(temp) as masterList.append(output_list(temp)), or even like this:
#in the end
with open("output.csv", "wb") as f:
writer = csv.writer(f, delimiter=',')
for i in masterList:
writer.writerow(output_list(i))
I have a file named report_data.csv that contains the following:
user,score
a,10
b,15
c,10
a,10
a,5
b,10
I am creating a dictionary from this file using this code:
with open('report_data.csv') as f:
f.readline() # Skip over the column titles
mydict = dict(csv.reader(f, delimiter=','))
After running this code mydict is:
mydict = {'a':5,'b':10,'c':10}
But I want it to be:
mydict = {'a':25,'b':25,'c':10}
In other words, whenever a key that already exists in mydict is encountered while reading a line of the file, the new value in mydict associated with that key should be the sum of the old value and the integer that appears on that line of the file. How can I do this?
The most straightforward way is to use defaultdict or Counter from useful collections module.
from collections import Counter
summary = Counter()
with open('report_data.csv') as f:
f.readline()
for line in f:
lbl, n = line.split(",")
n = int(n)
summary[lbl] = summary[lbl] + n
One of the most useful features in Counter class is the most_common() function, that is absent from the plain dictionaries and from defaultdict
This should work for you:
with open('report_data.csv') as f:
f.readline()
mydict = {}
for line in csv.reader(f, delimiter=','):
mydict[line[0]] = mydict.get(line[0], 0) + int(line[1])
try this.
mydict = {}
with open('report_data.csv') as f:
f.readline()
x = csv.reader(f, delimiter=',')
for x1 in x:
if mydict.get(x1[0]):
mydict[x1[0]] += int(x1[1])
else:
mydict[x1[0]] = int(x1[1])
print mydict
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.