I have a Problem with continues writing my datas in a csv-file. I want a program that detects, if there is a csv-file for my measurements-data. If not it would be generated. When the csv-file is new generated the datas are written in the csv-file on the column after the header with the variable cycle = 0.
If the csv-file exists, the datas should be written continuously after the last line of the csv. Also the variable cycle should continue.
I have written a program that can detect if there is a file or not but with the continuously lines I have problems.
I hope someone can help me.
# mes = Array with 20 spaces filled with the Numbers 0-19
date = time.strftime("%d/%m/%Y")
def write(cycle, mes):
if os.path.exists('/home/pi/Documents/Ventilatorprüfstand_Programm/out.csv') is True: #does the out.csv existate?
print("Do something")
out = open('out.csv', 'w')
data = [[cycle, mes[0],mes[1],mes[2],mes[3],mes[4],mes[5],mes[6],mes[7],mes[8],mes[9],mes[10],mes[11],mes[12],mes[13],mes[14],mes[15],mes[16],mes[17],mes[18],mes[19], date]]
line = cycle+1
for row in data:
for line in row:
out.write('%s;' % line)
out.write('\n')
out.close()
else:
print("Do another something")
header = lookuptable.names()
out = open('out.csv', 'w')
for row in header:
for column in row:
out.write('%s' % column)
out.write('\t')
out.write('\n')
data = [[cycle, mes[0],mes[1],mes[2],mes[3],mes[4],mes[5],mes[6],mes[7],mes[8],mes[9],mes[10],mes[11],mes[12],mes[13],mes[14],mes[15],mes[16],mes[17],mes[18],mes[19], date]]
for row in data:
for column in row:
out.write('%s;' % column)
out.write('\n')
out.close()`
When opening the file with open() there is the option 'a' to append the new lines to the end:
'a' open for writing, appending to the end of the file if it exists
Here is an example using the csv Python standard library:
import csv
import os
import random
headers = ['cycle', 'date', 'speed', 'temp', 'power']
new_data = [[random.randint(0, 100) for _ in range(3)] for _ in range(2)]
date = '00/01/02'
cycle = 1
# Copy the data and include the date and the cycle number:
full_rows = [ [cycle, date, *row] for row in new_data ]
filename = 'example.csv'
# Check if the file exist, if not create the file with header
if not os.path.exists(filename):
print('creating a new file')
with open(filename, 'w') as csvfile:
csvwriter = csv.writer(csvfile, delimiter=',')
csvwriter.writerow(headers) # add the header
# Append the data to the file
with open(filename, 'a', newline='') as csvfile: # note the 'a' option
csvwriter = csv.writer(csvfile, delimiter=',')
csvwriter.writerows(full_rows)
Related
I want to create a program which generates numbers from 0 to 100000 and stores it in a file then, remove the numbers i give as input
I have done the code for generating the numbers and storing them in a csv file
import csv
nums = list(range(0,100000))
with open('codes.csv', 'w') as f:
writer = csv.writer(f)
for val in nums:
writer.writerow([val])
and i tried to delete the row i wanted with this
import csv
import os
lines = list()
while True:
members= input("Please enter a number to be deleted: ")
with open('codes.csv', 'r') as readFile:
reader = csv.reader(readFile)
for row in reader:
lines.append(row)
for field in row:
if field == members:
lines.remove(row)
os.remove('codes.csv')
with open('codes.csv', 'a+') as writeFile:
writer = csv.writer(writeFile)
writer.writerows(lines)
but the file size is multiplying each time i remove a number, please help
Add check before appending to your list, something like this should work:
with open('codes.csv', 'r') as readFile:
reader = csv.reader(readFile)
for row in reader:
if all(field != members for field in row):
lines.append(row)
Ps: don't forget to clear lines by adding lines = [] at the beginning of the while loop (I assume you know what you're doing).
There a two problems:
The lines list is never cleared. Whenever a number is entered, everything is written again to lines.
When writing, the file is opened with the a+ attributes, which means "append and update" file.
Try to recreate the list within the outer while loop and override the file contents by opening the file with attribute w, like this:
import csv
import os
while True:
members= input("Please enter a number to be deleted: ")
lines = list()
with open('codes.csv', 'r') as readFile:
reader = csv.reader(readFile)
for row in reader:
lines.append(row)
for field in row:
if field == members:
lines.remove(row)
os.remove('codes.csv')
with open('codes.csv', 'w') as writeFile:
writer = csv.writer(writeFile)
writer.writerows(lines)
I'm trying to make a program which stores a list of names in a CSV file, and I'm trying to add a function to delete rows, which isn't working as it deletes everything in the CSV file.
I've tried using writer.writerow(row), which hasn't worked.
memberName = input("Please enter a member's name to be deleted.")
imp = open('mycsv.csv' , 'rb')
out = open('mycsv.csv' , 'wb')
writer = csv.writer(out)
for row in csv.reader(imp):
if row == memberName:
writer.writerow(row)
imp.close()
out.close()
I expected the program to only delete rows which contained memberName, but it deletes every row in the CSV file.
How do I change it to only delete a single row?
You can't write to the same file while reading it. Instead, use another file for output, e.g.:
import csv
member_name = input("Please enter a member's name to be deleted: ")
with open('in_file.csv') as in_file, open('out_file.csv', 'w') as out_file:
reader = csv.reader(in_file)
writer = csv.writer(out_file)
for row in reader:
if member_name not in row: # exclude a specific row
writer.writerow(row)
Alternatively, you could store needed rows in memory and write them back to the input file after resetting the file pointer:
import csv
member_name = input("Please enter a member's name to be deleted: ")
with open('in_file.csv', 'r+') as in_file:
reader = csv.reader(in_file)
rows = [row for row in csv.reader(in_file) if member_name not in row]
in_file.seek(0)
in_file.truncate()
writer = csv.writer(in_file)
writer.writerows(rows)
This worked for me: you could write the contents of the csv file to a list, then edit the list in python, then write the list back to the csv file.
lines = list()
memberName = input("Please enter a member's name to be deleted.")
with open('mycsv.csv', 'r') as readFile:
reader = csv.reader(readFile)
for row in reader:
lines.append(row)
for field in row:
if field == memberName:
lines.remove(row)
with open('mycsv.csv', 'w') as writeFile:
writer = csv.writer(writeFile)
writer.writerows(lines)
I am very new to Python programming and decided on a small project to learn the language.
Basically I am trying to:
Read the first cell of a CSV file.
Ask if that cell value is "liked".
If liked, write to the column next to the cell on 1., "1".
Else, write "0".
Repeat on next row until end of list.
My code right now:
import csv
reader = csv.reader(open("mylist.csv"), delimiter=',')
data = []
for row in reader:
data.append(row)
ask = (data[0][0])
ans = input("Do you like {}? ".format(ask))
if ans == ("y"):
f = open('mylist.csv', 'r')
reader = csv.reader(f)
data = list(reader)
f.close()
data[0][1] = '1'
my_new_list = open('mylist.csv', 'w', newline='')
csv_writer = csv.writer(my_new_list)
csv_writer.writerows(data)
my_new_list.close()
else:
f = open('mylist.csv', 'r')
reader = csv.reader(f)
data = list(reader)
f.close()
data[0][1] = '0'
my_new_list = open('mylist.csv', 'w', newline='')
csv_writer = csv.writer(my_new_list)
csv_writer.writerows(data)
my_new_list.close()
So basically, I am stuck trying to get the content of the next row.
FYI, I am looking to implement machine learning to this process.
First learning how to do this in a basic manner.
Any help is welcome.
Thank you!
You shouldn't read from and write to the same file/list/dict at the same time. If you do, references to data may change. You can start with something like this for your task. However, note that as the file grows you code becomes slower.
import csv
reader = csv.reader(open("test.csv", 'r'), delimiter=',')
content = []
for row in reader:
item = row[0]
ans = raw_input("Do you like {}? ".format(item))
if ans == 'y':
content.append([item, 1])
else:
content.append([item, 0])
writer = csv.writer(open('test.csv', 'w'))
writer.writerows(content)
In my last work with csv I opened the file so:
import csv
with open(name) as csvfile:
reader = csv.DictReader(csvfile)
for row in reader:
data.append(row)
If you want the resultant csv file to contain all of the data from the input file but with the question results added in, you could use something like this.
It will insert you answer (0 or 1) after the first item in each record.
import csv
reader = csv.reader(open("mylist.csv", 'r'), delimiter=',')
data = []
for row in reader:
data.append(row)
for row in data:
ans = raw_input("Do you like {}? ".format(row[0]))
if ans == 'y':
row[1:1] = "1"
else:
row[1:1] = "0"
writer = csv.writer(open('myresult.csv', 'w'))
writer.writerows(data)
I have an application that works. But in the interest of attempting to understand functions and python better. I am trying to split it out into various functions.
I"m stuck on the file_IO function. I'm sure the reason it does not work is because the main part of the application does not understand reader or writer. To better explain. Here is a full copy of the application.
Also I'm curious about using csv.DictReader and csv.DictWriter. Do either provide any advantages/disadvantages to the current code?
I suppose another way of doing this is via classes which honestly I would like to know how to do it that way as well.
#!/usr/bin/python
""" Description This script will take a csv file and parse it looking for specific criteria.
A new file is then created based of the original file name containing only the desired parsed criteria.
"""
import csv
import re
import sys
searched = ['aircheck', 'linkrunner at', 'onetouch at']
def find_group(row):
"""Return the group index of a row
0 if the row contains searched[0]
1 if the row contains searched[1]
etc
-1 if not found
"""
for col in row:
col = col.lower()
for j, s in enumerate(searched):
if s in col:
return j
return -1
#Prompt for File Name
def file_IO():
print "Please Enter a File Name, (Without .csv extension): ",
base_Name = raw_input()
print "You entered: ",base_Name
in_Name = base_Name + ".csv"
out_Name = base_Name + ".parsed.csv"
print "Input File: ", in_Name
print "OutPut Files: ", out_Name
#Opens Input file for read and output file to write.
in_File = open(in_Name, "rU")
reader = csv.reader(in_File)
out_File = open(out_Name, "wb")
writer = csv.writer(out_File, delimiter=',', quotechar='"', quoting=csv.QUOTE_ALL)
return (reader, writer)
file_IO()
# Read header
header = reader.next()
stored = []
writer.writerow([header[0], header[3]])
for i, row in enumerate(reader):
g = find_group(row)
if g >= 0:
stored.append((g, i, row))
stored.sort()
for g, i, row in stored:
writer.writerow([row[0], row[3]])
# Closing Input and Output files.
in_File.close()
out_File.close()
If I were you, I'd only separate find_group.
import csv
def find_group(row):
GROUPS = ['aircheck', 'linkrunner at', 'onetouch at']
for idx, group in enumerate(GROUPS):
if group in map(str.lower, row):
return idx
return -1
def get_filenames():
# this might be the only other thing you'd want to factor
# into a function, and frankly I don't really like getting
# user input this way anyway....
basename = raw_input("Enter a base filename (no extension): ")
infilename = basename + ".csv"
outfilename = basename + ".parsed.csv"
return infilename, outfilename
# notice that I don't open the files yet -- let main handle that
infilename, outfilename = get_filenames()
with open(infilename, 'rU') as inf, open(outfilename, 'wb') as outf:
reader = csv.reader(inf)
writer = csv.writer(outf, delimiter=',',
quotechar='"', quoting=csv.QUOTE_ALL)
header = next(reader)
writer.writerow([[header[0], header[3]])
stored = sorted([(find_group(row),idx,row) for idx,row in
enumerate(reader)) if find_group(row) >= 0])
for _, _, row in stored:
writer.writerow([row[0], row[3]])
#!/usr/bin/python
import csv
import re
string_1 = ('OneTouch AT')
string_2 = ('LinkRunner AT')
string_3 = ('AirCheck')
#searched = ['OneTouch AT', 'LinkRunner AT', 'AirCheck']
print "hello Pythong! "
#def does_match(string):
# stringl = string.lower()
# return any(s in stringl for s in searched)
inFile = open('data.csv', "rb")
reader = csv.reader(inFile)
outFile = open('data2.csv', "wb")
writer = csv.writer(outFile, delimiter='\t', quotechar='"', quoting=csv.QUOTE_ALL)
for row in reader:
found = False
for col in row:
if col in [string_1, string_2, string_3] and not found:
writer.writerow(row)
found = True
#for row in reader:
# if any(does_match(col) for col in row):
# writer.writerow(row[:2]) # write only 2 first columns
inFile.close()
outFile.close()
I'm trying to figure out how to search a CSV file for 3 items. If those items exist print the row. Ideally I would like only Columns 1 and 3 to print to a new file.
Sample Data File
LinkRunner AT Video,10,20
Wireless Performance Video OneTouch AT,1,2
Wired OneTouch AT,200,300
LinkRunner AT,200,300
AirCheck,200,300
I'm trying to figure out how to search a CSV file for 3 items. If
those items exist print the row. Ideally I would like only Columns 1
and 3 to print to a new file.
Try this:
import csv
search_for = ['OneTouch AT','LinkRunner AT','AirCheck']
with open('in.csv') as inf, open('out.csv','w') as outf:
reader = csv.reader(inf)
writer = csv.writer(outf, delimiter='\t', quotechar='"', quoting=csv.QUOTE_MINIMAL)
for row in reader:
if row[0] in search_for:
print('Found: {}'.format(row))
writer.writerow(row)
#!/usr/bin/python
import csv
import numpy as np
class search_csv(object):
def __init__(self, infile, outfile):
infile = open(infile, 'rb')
read_infile = [i for i in csv.reader(infile, delimiter='\t', quotechar='"', quoting=csv.QUOTE_MINIMAL)]
self.non_numpy_data = read_infile
self.data = np.array(read_infile, dtype=None)
self.outfile = open(outfile, 'wb')
self.writer_ = csv.writer(self.outfile, delimiter='\t', quotechar='"', quoting=csv.QUOTE_MINIMAL)
def write_to(self, matched_values):
self.writer_.writerows(matched_values)
print ' Matched Values Written '
return True
def searcher(self, items, return_cols=[0,2]): ##// items should be passed as list -> ['OneTouch AT', 'LinkRunner AT', 'AirCheck']
find_these = np.array(items, dtype=None)
matching_y = np.in1d(self.data, find_these).reshape(self.data.shape).nonzero()[0]
matching_data = self.data[matching_y][:,return_cols]
self.write_to(matching_data)
self.outfile.close()
return True
def non_numpy_search(self, items, return_cols=[0,2]):
lst = []
for i in self.non_numpy_data:
for ii in items:
if ii in i:
z = []
for idx in return_cols:
z.append(i[idx])
lst.append(z)
break
self.write_to(lst)
return True
### now use the class ###
SEARCHING_FOR = ['OneTouch AT', 'LinkRunner AT', 'AirCheck']
IN_FILE = 'in_file.csv'
OUT_FILE = 'out_file.csv'
non_numpy_search(IN_FILE, OUT_FILE).non_numpy_search(SEARCHING_FOR)
By the phrasing of your question I'm assuming you just want to complete the task at hand and don't really care how. So copy and paste this in and use your data file as the 'IN_FILE' value and the file name you want to write to as the 'OUT_FILE' value. Place the values you want to search for in the 'SEARCHING_FOR' list as you're done.
Things to note....
SEARCHING_FOR should be a list.
the values in SEARCHING_FOR are matched EXACTLY so 'A' will not match 'a'. If you want a to use a regex or something more complex let me know.
In function 'non_numpy_search' there is a 'return_cols' parameter. It defaults to the first and 3rd column.
If you don't have numpy let me know.
#!/usr/bin/python
import csv
import re
import sys
import gdata.docs.service
#string_1 = ('OneTouch AT')
#string_2 = ('LinkRunner AT')
#string_3 = ('AirCheck')
searched = ['aircheck', 'linkrunner at', 'onetouch at']
def find_group(row):
"""Return the group index of a row
0 if the row contains searched[0]
1 if the row contains searched[1]
etc
-1 if not found
"""
for col in row:
col = col.lower()
for j, s in enumerate(searched):
if s in col:
return j
return -1
def does_match(string):
stringl = string.lower()
return any(s in stringl for s in searched)
#Opens Input file for read and output file to write.
inFile = open('data.csv', "rb")
reader = csv.reader(inFile)
outFile = open('data2.csv', "wb")
writer = csv.writer(outFile, delimiter='\t', quotechar='"', quoting=csv.QUOTE_ALL)
#for row in reader:
# found = False
# for col in row:
# if col in [string_1, string_2, string_3] and not found:
# writer.writerow(row)
# found = True
"""Built a list of items to sort. If row 12 contains 'LinkRunner AT' (group 1),
one stores a triple (1, 12, row)
When the triples are sorted later, all rows in group 0 will come first, then
all rows in group 1, etc.
"""
stored = []
for i, row in enumerate(reader):
g = find_group(row)
if g >= 0:
stored.append((g, i, row))
stored.sort()
for g, i, row in stored:
writer.writerow(tuple(row[k] for k in (0,2))) # output col 1 & 5
#for row in reader:
# if any(does_match(col) for col in row):
# writer.writerow(row[:2]) # write only 2 first columns
# Closing Input and Output files.
inFile.close()
outFile.close()