Write to CSV without including (") in each record - python-3.x

I've shaped the data with pandas. And when I write to csv, there's the (") at the start and end of the row in the file.
"A|ColA|ColB|ColC|"
"A|val1|val2|val3|"
"A|val4|val5|val6|"
How do I write to csv such that the file becomes like this?
A|ColA|ColB|ColC|
A|val1|val2|val3|
A|val4|val5|val6|

Your dataframe already contains the quotes as part of the field and | was not recognized as a field separator. Was that intended?
If you want to force pandas just not to use quotes when writing, you can use quoting=csv.QUOTE_NONE as follows:
import csv
df.to_csv("mytext.txt", index = False, header = False, quoting=csv.QUOTE_NONE)
If you want to read it in again later into separate colums, you can do that like this:
pd.read_csv('mytext.txt', sep='|')

Related

What is the appropriate way to take in files that have a filename with a timestamp in it?

What is the appropriate way to take in files that have a filename with a timestamp in it and read properly?
One way I'm thinking of so far is to take these filenames into one single text file to read all at once.
For example, filenames such as
1573449076_1570501819_file1.txt
1573449076_1570501819_file2.txt
1573449076_1570501819_file3.txt
Go into a file named filenames.txt
Then something like
with open('/Documents/filenames.txt', 'r') as f:
for item in f:
if item.is_file():
file_stat = os.stat(item)
item = item.replace('\n', '')
print("Fetching {}".format(convert_times(file_stat)))
My question is how would I go about this where I can properly read the names in the text file given that they have timestamps in the actual names? Once figuring that out I can convert them.
If you just want to get the timestamps from the file names, assuming that they all use the same naming convention, you can do so like this:
import glob
import os
from datetime import datetime
# Grab all .txt files in the specified directory
files = glob.glob("<path_to_dir>/*.txt")
for file in files:
file = os.path.basename(file)
# Check that it contains an underscore
if not '_' in file:
continue
# Split the file name using the underscore as the delimiter
stamps = file.split('_')
# Convert the epoch to a legible string
start = datetime.fromtimestamp(int(stamps[0])).strftime("%c")
end = datetime.fromtimestamp(int(stamps[1])).strftime("%c")
# Consume the data
print(f"{start} - {end}")
...
You'll want to add some error checking and handling; for instance, if the first or second index in the stamps array isn't a parsable int, this will fail.

Remove double quotes while printing string in dataframe to text file

I have a dataframe which contains one column with multiple strings. Here is what the data looks like:
Value
EU-1050-22345,201908 XYZ DETAILS, CD_123_123;CD_123_124,2;1
There are almost 100,000 such rows in the dataframe. I want to write this data into a text file.
For this, I tried the following:
df.to_csv(filename, header=None,index=None,mode='a')
But I am getting the entire string in quotes when I do this. The output I obtain is:
"EU-1050-22345,201908 XYZ DETAILS, CD_123_123;CD_123_124,2;1"
But what I want is:
EU-1050-22345,201908 XYZ DETAILS, CD_123_123;CD_123_124,2;1 -> No Quotes
I also tried this:
df.to_csv(filename,header=None,index=None,mode='a',
quoting=csv.QUOTE_NONE)
However, I get an error that an escapechar is required. If i add escapechar='/' into the code, I get '/' in multiple places (but no quotes). I don't want the '/' either.
Is there anyway I can remove the quotes while writing into a text file WITHOUT adding any other escape characters ?
Based on OP's comment, I believe the semicolon is messing things up. I no longer have unwanted \ if using tabs to delimit csv.
import pandas as pd
import csv
df = pd.DataFrame(columns=['col'])
df.loc[0] = "EU-1050-22345,201908 XYZ DETAILS, CD_123_123;CD_123_124,2;1"
df.to_csv("out.csv", sep="\t", quoting=csv.QUOTE_NONE, quotechar="", escapechar="")
Original Answer:
According to this answer, you need to specify escapechar="\\" to use csv.QUOTE_NONE.
Have you tried:
df.to_csv("out.csv", sep=",", quoting=csv.QUOTE_NONE, quotechar="", escapechar="\\")
I was able to write a df to a csv using a single space as the separator and get the "quotes" around strings removed by replacing existing in-string spaces in the dataframe with non-breaking spaces before I wrote it as as csv.
df = df.applymap(lambda x: str(x).replace(' ', u"\u00A0"))
df.to_csv(outpath+filename, header=True, index=None, sep=' ', mode='a')
I couldn't use a tab delimited file for what I was writing output for, though that solution also works using additional keywords to df.to_csv(): quoting=csv.QUOTE_NONE, quotechar="", escapechar="")

Trouble writing a header line with a comma to an Excel csv file

I'm trying to write a simple header line in Intel Fortran (containing actual content commas) to an Excel csv. What I'd like to see in the first two columns is:
FMG(1,1) FMG(2,1)
Enclosing each term in quotes "FGM(i,j)" worked when I did it line by line:
Code: write (*,*) "FMG(1,1), kg/s (O2): ", FMG(1,1)
Output: FMG(1,1), kg/s (O2): 0.129000000000000
Some of the things I've tried include:
code: write (10,*) "FMG(1,1)","FMG(2,1)"
csv column output: FMG(1 1)FMG(2 1)
code: write (10,*) "FMG(1,1)" , "FMG(2,1)"
csv column output: FMG(1 1)FMG(2 1) (same thing)
code: write (10,*) " FMG(1,1)," "FMG(2,1)"
csv column output: FMG(1 1) FMG(2,1)
got the 2nd one correctly
CSV by name means Comma Separated Values. If you output "FMG(1,1),FMG(1,2)" then removing the commas, you will get
FMG(1
1)
FMG(1
2)
which is what you are seeing. To include the commas, the strings need to be enclosed in quotes. If you write
write (10,*) '"FMG(1,1)","FMG(2,1)"'
it might achieve what you are looking for.

removing extra column in a csv file while exporting data using python3

I wrote a function in python3 which merges some files in the same directory and returns a csv file as the output but the problem with csv file is that I get one extra column at the beginning which does not have header and the other rows of that columns are numbers starting from 0. do you know how I write the csv file without getting the extra column?
you can split by ,, and then use slicing to remove the first element.
example:
original = """col1,col2,col3
0,val01,val02,val03
1,val11,val12,val13
2,val21,val22,val23
"""
original_lines = original.splitlines()
result = original_lines[:1] # copy header
for line in original_lines[1:]:
result.append(','.join(line.split(',')[1:]))
print('\n'.join(result))
Output:
col1,col2,col3
val01,val02,val03
val11,val12,val13
val21,val22,val23

Error in reading a ascii encoded csv file?

I have a csv file named Qid-NamedEntityMapping.csv having data like this:
Q1000070 b'Myron V. George'
Q1000296 b'Fred (footballer, born 1979)'
Q1000799 b'Herbert Greenfield'
Q1000841 b'Stephen A. Northway'
Q1001203 b'Buddy Greco'
Q100122 b'Kurt Kreuger'
Q1001240 b'Buddy Lester'
Q1001867 b'Fyodor Stravinsky'
The second column is 'ascii' encoded, and when I am reading the file using the following code, then also it not being read properly:
import chardet
import pandas as pd
def find_encoding(fname):
r_file = open(fname, 'rb').read()
result = chardet.detect(r_file)
charenc = result['encoding']
return charenc
my_encoding = find_encoding('datasets/KGfacts/Qid-
NamedEntityMapping.csv')
df = pd.read_csv('datasets/KGfacts/Qid-
NamedEntityMapping.csv',error_bad_lines=False, encoding=my_encoding)
But the output looks like this:
Also, I tried to use encoding='UTF-8'. but still, the output is the same.
What can be done to read it properly?
Looks like you have an improperly saved TSV file. Once you circumvent the TAB problem (as suggested in my comment), you can convert the column with names to a more suitable representation.
Let's assume that the second column of the dataframe is called "names". The b'XXX' thing is probably a bytes [mis]representation of a string. Convert it to a bytes object with ast.literal_eval and then decode to a string:
import ast
df["names"].apply(ast.literal_eval).apply(bytes.decode)
#0 Myron...
#1 Fred...
Last but not least, your problem has almost nothing to do with encodings or charsets.
Your issue looks like the CSV is actually tab separated; so you need to have sep='\t' in the read_csv function. It's reading everything else as a single column, except "born 1979" in the first row, as that is the only cell with a comma in it.

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