reading from file and manipulate in python - python

I have a text file:
it can change each time and the number of lines can be changed, and contains the following for each line:
string (can contain one word, two or even more) ^ string of one word
EX:
level country ^ layla
hello sandra ^ organization
hello people ^ layla
hello samar ^ organization
I want to create dataframe using pandas such that:
item0 ( country, people)
item1 (sandra , samar)
Because for example each time there layla, we are returning the most right name that belongs to it and added it as the second column just shown above which is in this case ( country, people), and we called layla as item0 and as the index of the dataframe. I can't seem to arrange this and I don't know how to do the logic for returning the duplicated of whatever after the "^" and returning the list of its belonged most right name. My trial so far which doesn't really do it is:
def text_file(file):
list=[]
file_of_text = "text.txt"
with open(file_of_context) as f:
for l in f:
l_dict = l.split(" ")
list.append(l_dict)
return(list)
def items(file_of_text):
list_of_items= text_file(file_of_text)
for a in list_of_items:
for b in a:
if a[-1]==
def main():
file_of_text = "text.txt"
if __name__ == "__main__":
main()

Starting with pandas read_csv() Specifying '^' as your delimiter and using arbitrary column names
df = pd.read_csv('data.csv', delimiter='\^', names=['A', 'B'])
print (df)
A B
0 level country layla
1 hello sandra organization
2 hello people layla
3 hello samar organization
then we split to get the values we want. That expand arg is new in pandas 16 I believe
df['A'] = df['A'].str.split(' ', expand=True)[1]
print(df)
A B
0 country layla
1 sandra organization
2 people layla
3 samar organization
then we group column B and apply the tuple function. Note: We're reseting the index so we can use it later
g = df.groupby('B')['A'].apply(tuple).reset_index()
print(g)
B A
0 layla (country, people)
1 organization (sandra, samar)
Creating a new column with the string 'item' and the index
g['item'] = 'item' + g.index.astype(str)
print (g[['item','A']])
item A
0 item0 (country, people)
1 item1 (sandra, samar)

Let's assume that your file is called file_of_text.txt and contains the following:
level country ^ layla
hello sandra ^ organization
hello people ^ layla
hello samar ^ organization
You can get your data from a file to a dataframe similar to your desired output with the following lines of code:
import re
import pandas as pd
def main(myfile):
# Open the file and read the lines
text = open(myfile,'r').readlines()
# Split the lines into lists
text = list(map(lambda x: re.split(r"\s[\^\s]*",x.strip()), text))
# Put it in a DataFrame
data = pd.DataFrame(text, columns = ['A','B','C'])
# Create an output DataFrame with rows "item0" and "item1"
final_data = pd.DataFrame(['item0','item1'],columns=['D'])
# Create your desired column
final_data['E'] = data.groupby('C')['B'].apply(lambda x: tuple(x.values)).values
print(final_data)
if __name__ == "__main__":
myfile = "file_of_text.txt"
main(myfile)
The idea is to read the lines from the text file and then split each line using the split method from the re module. The result is then passed to the DataFrame method to generate a dataframe called data, which is used to create the desired dataframe final_data. The result should look like the following:
# data
A B C
0 level country layla
1 hello sandra organization
2 hello people layla
3 hello samar organization
# final_data
D E
0 item0 (country, people)
1 item1 (sandra, samar)
Please take a look at the script and ask further questions, if you have any.
I hope this helps.

Related

Splitting column by multiple custom delimiters in Python

I need to split a column called Creative where each cell contains samples such as:
pn(2021)io(302)ta(Yes)pt(Blue)cn(John)cs(Doe)
Where each two-letter code preceding each bubbled section ( ) is the title of the desired column, and are the same in every row. The only data that changes is what is inside the bubbles. I want the data to look like:
pn
io
ta
pt
cn
cs
2021
302
Yes
Blue
John
Doe
I tried
df[['Creative', 'Creative Size']] = df['Creative'].str.split('cs(',expand=True)
and
df['Creative Size'] = df['Creative Size'].str.replace(')','')
but got an error, error: missing ), unterminated subpattern at position 2, assuming it has something to do with regular expressions.
Is there an easy way to split these ? Thanks.
Use extract with named capturing groups (see here):
import pandas as pd
# toy example
df = pd.DataFrame(data=[["pn(2021)io(302)ta(Yes)pt(Blue)cn(John)cs(Doe)"]], columns=["Creative"])
# extract with a named capturing group
res = df["Creative"].str.extract(
r"pn\((?P<pn>\d+)\)io\((?P<io>\d+)\)ta\((?P<ta>\w+)\)pt\((?P<pt>\w+)\)cn\((?P<cn>\w+)\)cs\((?P<cs>\w+)\)",
expand=True)
print(res)
Output
pn io ta pt cn cs
0 2021 302 Yes Blue John Doe
I'd use regex to generate a list of dictionaries via comprehensions. The idea is to create a list of dictionaries that each represent rows of the desired dataframe, then constructing a dataframe out of it. I can build it in one nested comprehension:
import re
rows = [{r[0]:r[1] for r in re.findall(r'(\w{2})\((.+)\)', c)} for c in df['Creative']]
subtable = pd.DataFrame(rows)
for col in subtable.columns:
df[col] = subtable[col].values
Basically, I regex search for instances of ab(*) and capture the two-letter prefix and the contents of the parenthesis and store them in a list of tuples. Then I create a dictionary out of the list of tuples, each of which is essentially a row like the one you display in your question. Then, I put them into a data frame and insert each of those columns into the original data frame. Let me know if this is confusing in any way!
David
Try with extractall:
names = df["Creative"].str.extractall("(.*?)\(.*?\)").loc[0][0].tolist()
output = df["Creative"].str.extractall("\((.*?)\)").unstack()[0].set_axis(names, axis=1)
>>> output
pn io ta pt cn cs
0 2021 302 Yes Blue John Doe
1 2020 301 No Red Jane Doe
Input df:
df = pd.DataFrame({"Creative": ["pn(2021)io(302)ta(Yes)pt(Blue)cn(John)cs(Doe)",
"pn(2020)io(301)ta(No)pt(Red)cn(Jane)cs(Doe)"]})
We can use str.findall to extract matching column name-value pairs
pd.DataFrame(map(dict, df['Creative'].str.findall(r'(\w+)\((\w+)')))
pn io ta pt cn cs
0 2021 302 Yes Blue John Doe
Using regular expressions, different way of packaging final DataFrame:
import re
import pandas as pd
txt = 'pn(2021)io(302)ta(Yes)pt(Blue)cn(John)cs(Doe)'
data = list(zip(*re.findall('([^\(]+)\(([^\)]+)\)', txt))
df = pd.DataFrame([data[1]], columns=data[0])

Panda module export, split data

I'm trying to read a .txt file and output the count of each letter which works, however, I'm having trouble exporting that data to .csv in a specific way.
A snippet of the code:
freqs = {}
with open(Book1) as f:
for line in f:
for char in line:
if char in freqs:
freqs[char] += 1
else:
freqs[char] = 1
print(freqs)
And for the exporting to csv, I did the following:
test = {'Book 1 Output':[freqs]}
df = pd.DataFrame(test, columns=['Book 1 Output'])
df.to_csv(r'book_export.csv', sep=',')
Currently when I run it, the export looks like this (Manually done):
However I want the output to be each individual row, so it should look something like this when I open it:
I want it to separate it from the ":" and "," into 3 different columns.
I've tried various other answers on here but most of them end up with giving ValueErrors so maybe I just don't know how to apply it like the following one.
df[[',']] = df[','].str.split(expand=True)
Use DataFrame.from_dict with DataFrame.rename_axis for set index name, then csv looks like you need:
#sample data
freqs = {'a':5,'b':2}
df = (pd.DataFrame.from_dict(freqs, orient='index',columns=['Book 1 Output'])
.rename_axis('Letter'))
print (df)
Book 1 Output
Letter
a 5
b 2
df.to_csv(r'book_export.csv', sep=',')
Or alternative is use Series:
s = pd.Series(freqs, name='Book 1 Output').rename_axis('Letter')
print (s)
Letter
a 5
b 2
Name: Book 1 Output, dtype: int64
s.to_csv(r'book_export.csv', sep=',')
EDIT:
If there are multiple frequencies change DataFrame constructor:
freqs = {'a':5,'b':2}
freqs1 = {'a':9,'b':3}
df = pd.DataFrame({'f1':freqs, 'f2':freqs1}).rename_axis('Letter')
print (df)
f1 f2
Letter
a 5 9
b 2 3

replace the text in one column with a dictionary in other column

I have texts in one column and respective dictionary in another column. I have tokenized the text and want to replace those tokens which found a match for the key in respective dictionary. the text and and the dictionary are specific to each record of a pandas dataframe.
import pandas as pd
data =[['1','i love mangoes',{'love':'hate'}],['2', 'its been a long time we have not met',{'met':'meet'}],['3','i got a call from one of our friends',{'call':'phone call','one':'couple of'}]]
df = pd.DataFrame(data, columns = ['id', 'text','dictionary'])
The final dataframe the output should be
data =[['1','i hate mangoes'],['2', 'its been a long time we have not meet'],['3','i got a phone call from couple of of our friends']
df = pd.DataFrame(data, columns =['id, 'modified_text'])
I am using Python 3 in a windows machine
You can use dict.get method after zipping the 2 cols and splitting the sentence:
df['modified_text']=([' '.join([b.get(i,i) for i in a.split()])
for a,b in zip(df['text'],df['dictionary'])])
print(df)
Output:
id text \
0 1 i love mangoes
1 2 its been a long time we have not met
2 3 i got a call from one of our friends
dictionary \
0 {'love': 'hate'}
1 {'met': 'meet'}
2 {'call': 'phone call', 'one': 'couple of'}
modified_text
0 i hate mangoes
1 its been a long time we have not meet
2 i got a phone call from couple of of our friends
I added spaces to the key and values to distinguish a whole word from part of it:
def replace(text, mapping):
new_s = text
for key in mapping:
k = ' '+key+' '
val = ' '+mapping[key]+' '
new_s = new_s.replace(k, val)
return new_s
df_out = (df.assign(modified_text=lambda f:
f.apply(lambda row: replace(row.text, row.dictionary), axis=1))
[['id', 'modified_text']])
print(df_out)
id modified_text
0 1 i hate mangoes
1 2 its been a long time we have not met
2 3 i got a phone call from couple of of our friends

how to get the word case from the text while pattern matching in python

I have a data frame with two columns Stg and Txt. The task is to check for all of the words in Stg Column with each Txt row and output the matched words into a new column while keeping the word case as in the Txt.
Example Code:
from pandas import DataFrame
new = {'Stg': ['way','Early','phone','allowed','type','brand name'],
'Txt': ['An early term','two-way allowed','New Phone feature that allowed','amazing universe','new day','the brand name is stage']
}
df = DataFrame(new,columns= ['Stg','Txt'])
my_list = df["Stg"].tolist()
import re
def words_in_string(word_list, a_string):
word_set = set(word_list)
pattern = r'\b({0})\b'.format('|'.join(word_list))
for found_word in re.finditer(pattern, a_string):
word = found_word.group(0)
if word in word_set:
word_set.discard(word)
yield word
if not word_set:
raise StopIteration
df['new'] = ''
for i,values in enumerate(df['Txt']):
a=[]
b = []
for word in words_in_string(my_list, values):
a=word
b.append(a)
df['new'][i] = b
exit
The above code returns the case from the Stg column. Is there a way to get the case from Txt. Also I want to check for the entire string and not the substring like in the case of the text 'two-way', the current code returns the word way.
Current Output:
Stg Txt new
0 way An early term []
1 Early two-way allowed [way, allowed]
2 phone New Phone feature that allowed [allowed]
3 allowed amazing universe []
4 type new day []
5 brand name the brand name is stage [brand name]
Expected Output:
Stg Txt new
0 way An early term [early]
1 Early two-way allowed [allowed]
2 phone New Phone feature that allowed [Phone, allowed]
3 allowed amazing universe []
4 type new day []
5 brand name the brand name is stage [brand name]
You should use Series.str.findall with negative lookbehind:
import pandas as pd
import re
new = {'Stg': ['way','Early','phone','allowed','type','brand name'],
'Txt': ['An early term','two-way allowed','New Phone feature that allowed','amazing universe','new day','the brand name is stage']
}
df = pd.DataFrame(new,columns= ['Stg','Txt'])
pattern = "|".join(f"\w*(?<![A-Za-z-;:,/|]){i}\\b" for i in new["Stg"])
df["new"] = df["Txt"].str.findall(pattern, flags=re.IGNORECASE)
print (df)
#
Stg Txt new
0 way An early term [early]
1 Early two-way allowed [allowed]
2 phone New Phone feature that allowed [Phone, allowed]
3 allowed amazing universe []
4 type new day []
5 brand name the brand name is stage [brand name]

Extract prefix from string in dataframe column where exists in a list

Looking for some help.
I have a pandas dataframe column and I want to extract the prefix where such prefix exists in a separate list.
pr_list = ['1 FO-','2 IA-']
Column in df is like
PartNumber
ABC
DEF
1 FO-BLABLA
2 IA-EXAMPLE
What I am looking for is to extract the prefix where present, put in a new column and leave the rest of the string in the original column.
PartNumber Prefix
ABC
DEF
BLABLA 1 FO-
EXAMPLE 2 IA-
Have tried some things like str.startswith but a bit of a python novice and wasn't able to get it to work.
much appreciated
EDIT
Both solutions below work on the test data, however I am getting an error
error: nothing to repeat at position 16
Which suggests something askew in my dataset. Not sure what position 16 refers to but looking at both the prefix list and PartNumber column in position 16 nothing seems out of the ordinary?
EDIT 2
I have traced it to have an * in the pr_list seems to be throwing it. is * some reserved character? is there a way to break it out so it is read as text?
You can try:
df['Prefix']=df.PartNumber.str.extract(r'({})'.format('|'.join(pr_list))).fillna('')
df.PartNumber=df.PartNumber.str.replace('|'.join(pr_list),'')
print(df)
PartNumber Prefix
0 ABC
1 DEF
2 BLABLA 1 FO-
3 EXAMPLE 2 IA-
Maybe it's not what you are looking for, but may it help.
import pandas as pd
pr_list = ['1 FO-','2 IA-']
df = pd.DataFrame({'PartNumber':['ABC','DEF','1 FO-BLABLA','2 IA-EXAMPLE']})
extr = '|'.join(x for x in pr_list)
df['Prefix'] = df['PartNumber'].str.extract('('+ extr + ')', expand=False).fillna('')
df['PartNumber'] = df['PartNumber'].str.replace('|'.join(pr_list),'')
df

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