I am trying to export data from Ansys Mechanical by writing into a csv file. Unfortunately with my code the charakters in my lists don´t get seperated by the comma. They just end up in one cell and I can't figure out why. Thanks allot
Here are an example of my code and results
import csv
csv_outfile = r'Z:\Ansys\05-11-2022_output.csv'
with open(csv_outfile, 'wb') as ofile:
write = csv.writer(ofile)
write.writerow(['1' ,'2' ,'3'])
with open('test.csv', 'w') as ofile:
write = csv.writer(ofile)
write.writerow(i for i in ['1' ,'2' ,'3']) #
Change wb to w Because you write numbers
Related
Trying to save the output to a csv file. Below prints the information to the screen fine but when I try to save it to a csv or text file, I get one letter at a time. Trying to understand why.
data = json.loads(response.text)
info = data['adapterInstancesInfoDto']
for x in range(len(info)):
val = info[x]['resourceKey']['name']
print(val)
Tried writing to a csv and text file same issue. Tried Pandas same result. I am thinking I need to convert it into a tuple or diction to save to a csv file.
Use the built-in module csv for working with csv files:
Here's a example for writing to the file:
import csv
with open('filename.csv', 'w', newline='') as file:
writer = csv.writer(file)
writer.writerow(["SNo", "Name"])
writer.writerow([1, "Python"])
writer.writerow([2, "Csv"])
I'm attempting to rewrite specific cells in a csv file using Python.
However, whenever I try to modify an aspect of the csv file, the csv file ends up being emptied (the file contents becomes blank).
Minimal code example:
import csv
ReadFile = open("./Resources/File.csv", "rt", encoding = "utf-8-sig")
Reader = csv.reader(ReadFile)
WriteFile = open("./Resources/File.csv", "wt", encoding = "utf-8-sig")
Writer = csv.writer(WriteFile)
for row in Reader:
row[3] = 4
Writer.writerow(row)
ReadFile.close()
WriteFile.close()
'File.csv' looks like this:
1,2,3,FOUR,5
1,2,3,FOUR,5
1,2,3,FOUR,5
1,2,3,FOUR,5
1,2,3,FOUR,5
In this example, I'm attempting to change 'FOUR' to '4'.
Upon running this code, the csv file becomes empty instead.
So far, the only other question related to this that I've managed to find is this one, which does not seem to be dealing with rewriting specific cells in a csv file but instead deals with writing new rows to a csv file.
I'd be very grateful for any help anyone reading this could provide.
The following should work:
import csv
with open("./Resources/File.csv", "rt", encoding = "utf-8-sig") as ReadFile:
lines = list(csv.reader(ReadFile))
with open("./Resources/File.csv", "wt", encoding = "utf-8-sig") as WriteFile:
Writer = csv.writer(WriteFile)
for line in lines:
line[3] = 4
Writer.writerow(line)
When you open a writer with w option, it will delete the contents and start writing the file anew. The file is therefore, at the point when you start to read, empty.
Try writing to another file (like FileTemp.csv) and at the end of the program renaming FileTemp.csv to File.csv.
I'm having some trouble with some test code. This code is meant to:
read a csv file
take two inputs
put the inputs in a list
make a new list with the csv contents + the input list
overwrite the csv with the new list.
import csv
input1 = input("input 1")
input2 = input("input 2")
original = []
with open('test.csv', 'r') as f:
reader = csv.reader(f)
original = list(reader)
data = [input1,input2]
original.append(data)
with open('test.csv', 'w') as f:
writer = csv.writer(f)
writer.writerows(original)
For example, if 'cats' and 'dogs' were in the file, and I typed in 'zebras' and 'giraffes', I'd expect the csv to look like this when I open it in Notepad:
link
However blank lines are produced in between the lists when I run the code more than once, and I don't know why.
link
I am new to Python and any help is appreciated.
The solution is:
open('test.csv', 'w', newline='')
In new versions of Python csv.Writer now handles newline, but open also does. Then you must tell open that it must not add newline when writing to the file. See API documentation for more explanations.
I have a large file from a proprietary archive format. Unzipping this archive gives a file that has no extension, but the data inside is comma-delimited. Adding a .csv extension or simply opening the file with Excel will work.
I have about 375-400 of these files, and I'm trying to extract a chunk of rows (about 13,500 out of 1.2M+ rows) between a keyword "Point A" and another keyword "Point B".
I found some code on this site that I think is extracting the data correctly, but I'm getting an error:
AttributeError: 'list' object has no attribute 'rows'
when trying to save out the file. Can somebody help me get this data to save into a csv?
import re
import csv
import time
print(time.ctime())
file = open('C:/Users/User/Desktop/File with No Extension That\'s Very Similar to CSV', 'r')
data = file.read()
x = re.findall(r'Point A(.*?)Point B', data,re.DOTALL)
name = "C:/Users/User/Desktop/testoutput.csv"
with open(name, 'w', newline='') as file2:
savefile = csv.writer(file2)
for i in x.rows:
savefile.writerow([cell.value for cell in i])
print(time.ctime())
Thanks in advance, any help would be much appreciated.
The following should work nicely. As mentioned, your regex usage was almost correct. It is possible to still use the Python CSV library to do the CSV processing by converting the found text into a StringIO object and passing that to the CSV reader:
import re
import csv
import time
import StringIO
print(time.ctime())
input_name = "C:/Users/User/Desktop/File with No Extension That's Very Similar to CSV"
output_name = "C:/Users/User/Desktop/testoutput.csv"
with open(input_name, 'r') as f_input, open(output_name, 'wb') as f_output:
# Read whole file in
all_input = f_input.read()
# Extract interesting lines
ab_input = re.findall(r'Point A(.*?)Point B', all_input, re.DOTALL)[0]
# Convert into a file object and parse using the CSV reader
fab_input = StringIO.StringIO(ab_input)
csv_input = csv.reader(fab_input)
csv_output = csv.writer(f_output)
# Iterate a row at a time from the input
for input_row in csv_input:
# Skip any empty rows
if input_row:
# Write row at a time to the output
csv_output.writerow(input_row)
print(time.ctime())
You have not given us an example from your CSV file, so if there are problems, you might need to configure the CSV 'dialect' to process it better.
Tested using Python 2.7
You have 2 problems here: the first is related to the regular expression and the other is about the list syntax.
Getting what you want
The way you are using the regular expression will return to you a list with a single value (all lines into an unique string).
Probably there is a better way of doing this but I would go now with something like this:
with open('bla', 'r') as input:
data = input.read()
x = re.findall(r'Point A(.*?)Point B', data, re.DOTALL)[0]
x = x.splitlines(False)[1:]
That's not pretty but will return a list with all values between those two points.
Working with lists
There is no rows attribute inside lists. You just have to iterate over it:
for i in x:
do what you have to do
See, I'm not familiar to the csv library but it looks that you will have to perform some manipulations to the i value before adding it to the library.
IMHO, I would avoid using CSV format since it is kind of "locale dependent" so it may not work as expected depending the settings your end-users may have on OS.
Updating the code so that #Martin Evans answer works on the latest Python version.
import re
import csv
import time
import io
print(time.ctime())
input_name = "C:/Users/User/Desktop/File with No Extension That's Very Similar to CSV"
output_name = "C:/Users/User/Desktop/testoutput.csv"
with open(input_name, 'r') as f_input, open(output_name, 'wt') as f_output:
# Read whole file in
all_input = f_input.read()
# Extract interesting lines
ab_input = re.findall(r'Point A(.*?)Point B', all_input, re.DOTALL)[0]
# Convert into a file object and parse using the CSV reader
fab_input = io.StringIO(ab_input)
csv_input = csv.reader(fab_input)
csv_output = csv.writer(f_output)
# Iterate a row at a time from the input
for input_row in csv_input:
# Skip any empty rows
if input_row:
# Write row at a time to the output
csv_output.writerow(input_row)
print(time.ctime())
Also, by using 'wt' instead of 'wb' one can avoid
"TypeError: a bytes-like object is required, not 'str'"
I'm using Python's csv module to do some reading and writing of csv files.
I've got the reading fine and appending to the csv fine, but I want to be able to overwrite a specific row in the csv.
For reference, here's my reading and then writing code to append:
#reading
b = open("bottles.csv", "rb")
bottles = csv.reader(b)
bottle_list = []
bottle_list.extend(bottles)
b.close()
#appending
b=open('bottles.csv','a')
writer = csv.writer(b)
writer.writerow([bottle,emptyButtonCount,100, img])
b.close()
And I'm using basically the same for the overwrite mode(which isn't correct, it just overwrites the whole csv file):
b=open('bottles.csv','wb')
writer = csv.writer(b)
writer.writerow([bottle,btlnum,100,img])
b.close()
In the second case, how do I tell Python I need a specific row overwritten? I've scoured Gogle and other stackoverflow posts to no avail. I assume my limited programming knowledge is to blame rather than Google.
I will add to Steven Answer :
import csv
bottle_list = []
# Read all data from the csv file.
with open('a.csv', 'rb') as b:
bottles = csv.reader(b)
bottle_list.extend(bottles)
# data to override in the format {line_num_to_override:data_to_write}.
line_to_override = {1:['e', 'c', 'd'] }
# Write data to the csv file and replace the lines in the line_to_override dict.
with open('a.csv', 'wb') as b:
writer = csv.writer(b)
for line, row in enumerate(bottle_list):
data = line_to_override.get(line, row)
writer.writerow(data)
You cannot overwrite a single row in the CSV file. You'll have to write all the rows you want to a new file and then rename it back to the original file name.
Your pattern of usage may fit a database better than a CSV file. Look into the sqlite3 module for a lightweight database.