How to new line or separators in csv? - python-3.x

Not to over write csv, I tried 'a' but I get no separators.
Tried to replaced 'w' with 'a', but get no separator just mismash
import csv
with open('csv/1.n04', 'r') as csvFile:
reader = csv.reader(csvFile)
s = "".join(row[0] for row in reader)
a = s.count('0')
b = s.count('1')
csvFile.close()
import csv
f = open('csv/sum1.n04', 'w')
if b>=1:
f.write(str((a+b)/b))
else:
f.write(str(a))
f.close
import os
os.remove("csv/1.n04")
print ('Klar')
No error messages, it just over write csv file

Related

.csv to .arff function on Python

I'm trying to do a convertion function from csv to arff, right now I have this:
def csv2arff(csv_path, arff_path=None):
with open(csv_path, 'r') as fr:
attributes = []
if arff_path is None:
arff_path = csv_path[:-4] + '_prueba.arff' # *.arff -> *.csv
write_sw = False
with open(arff_path, 'w') as fw:
fw.write('#relation base_datos_modelo_3_limpia \n')
firstline = fr.readlines()[0].rstrip()
fw.write(firstline)
and that gives me:
#relation base_datos_modelo_3_limpia
DVJ_Valgus_KneeMedialDisplacement_D_discr,BMI,AgeGroup,ROM-PADF-KE_D,DVJ_Valgus_FPPA_D_discr,TrainFrequency,DVJ_Valgus_FPPA_ND_discr,Asym_SLCMJLanding-pVGRF(10percent)_discr,Asym-ROM-PHIR(≥8)_discr,Asym_TJ_Valgus_FPPA(10percent)_discr,TJ_Valgus_FPPA_ND_discr,Asym-ROM-PHF-KE(≥8)_discr,TJ_Valgus_FPPA_D_discr,Asym_SLCMJ-Height(10percent)_discr,Asym_YBTpl(10percent)_discr,Position,Asym-ROM-PADF-KE(≥8º)_discr,DVJ_Valgus_KneeMedialDisplacement_ND_discr,DVJ_Valgus_Knee-to-ankle-ratio_discr,Asym-ROM-PKF(≥8)_discr,Asym-ROM-PHABD(≥8)_discr,Asym-ROM-PHF-KF(≥8)_discr,Asym-ROM-PHER(≥8)_discr,AsymYBTanterior10percentdiscr,Asym-ROM-PHABD-HF(≥8)_discr,Asym-ROM-PHE(≥8)_discr,Asym(>4cm)-DVJ_Valgus_Knee;edialDisplacement_discr,Asym_SLCMJTakeOff-pVGRF(10percent)_discr,Asym-ROM-PHADD(≥8)_discr,Asym-YBTcomposite(10percent)_discr,Asym_SingleHop(10percent)_discr,Asym_YBTpm(10percent)_discr,Asym_DVJ_Valgus_FPPA(10percent)_discr,Asym_SLCMJ-pLFT(10percent)_discr,DominantLeg,Asym-ROM-PADF-KF(≥8)_discr,ROM-PHER_ND,CPRDmentalskills,POMStension,STAI-R,ROM-PHER_D,ROM-PHIR_D,ROM-PADF-KF_ND,ROM-PADF-KF_D,Age_at_PHV,ROM-PHIR_ND,CPRDtcohesion,Eperience,ROM-PHABD-HF_D,MaturityOffset,Weight,ROM-PHADD_ND,Height,ROM-PHADD_D,Age,POMSdepressio,ROM-PADF-KE_ND,POMSanger,YBTanterior_Dnorm,YBTanterior_NDnorm,POMSvigour,Soft-Tissue_injury_≥4days
So i want to put "#attribute" before each attribute and change the "," to "\n". But don't know how to do it, I tried to make a function to change the "," but didn't work, any idea?
Thank you guys.
Try the liac-arff library.
Here is an example for converting the UCI iris dataset from ARFF to CSV and then back to ARFF:
import csv
import arff
# arff -> csv
content = arff.load(open('./iris.arff', 'r'))
with open('./out.csv', 'w') as fp:
writer = csv.writer(fp)
header = []
for n, t in content['attributes']:
header.append(n)
writer.writerow(header)
writer.writerows(content['data'])
# csv -> arff
with open('./out.csv', 'r') as fp:
reader = csv.reader(fp)
header = None
data = []
for row in reader:
if header is None:
header = row
else:
data.append(row)
content = {}
content['relation'] = "from my csv file"
content['attributes'] = []
for n in header:
if n == "class":
content['attributes'].append((n, ['Iris-setosa', 'Iris-versicolor', 'Iris-virginica']))
else:
content['attributes'].append((n, 'NUMERIC'))
content['data'] = data
with open('./out.arff', 'w') as fp:
arff.dump(content, fp)
NB: For the last stage, we need to specify the nominal class values, which you could determine by scanning the data.

How do I remove first column in csv file?

I have a CSV file where the first row in the first column is blank with some numbers in the second and third row. This whole column is useless and I need to remove it so I can convert the data into a JSON file. I just need to know how to remove the first column of data so I can parse it. Any help is greatly appreciated!
My script is as follows
#!/usr/bin/python3
import pandas as pd
import csv, json
xls = pd.ExcelFile(r'C:\Users\Andy-\Desktop\Lab2Data.xlsx')
df = xls.parse(sheetname="Sheet1", index_col=None, na_values=['NA'])
df.to_csv('file.csv')
file = open('file.csv', 'r')
lines = file.readlines()
file.close()
data = {}
with open('file.csv') as csvFile:
csvReader = csv.DictReader(csvFile)
for rows in csvReader:
id = rows['Id']
data[id] = rows
with open('Lab2.json', 'w') as jsonFile:
jsonFile.write(json.dumps(data, indent=4))
I don't know much about json files but this will remove the first column from your csv file.
with open ('new_file.csv', 'w') as out_file :
with open ('file.csv') as in_file :
for line in in_file :
test_string = line.strip ('\n').split (',')
out_file.write (','.join (test_string [1:]) + '\n')

How to read a column and write it as a row in python?

I am trying to read a csv and then transpose one column into a row.
I tried following a tutorial for reading a csv and then one for writing but the data doesnt stay saved to the list when I try to write the row.
import csv
f = open('bond-dist-rep.csv')
csv_f = csv.reader(f)
bondlength = []
with open("bond-dist-rep.csv") as f:
for row in csv_f:
bondlength.append(row[1])
print (bondlength)
print (len(bondlength))
with open('joined.csv', 'w', newline='') as csvfile:
csv_a = csv.writer (csvfile, delimiter=',',quotechar='"',
quoting=csv.QUOTE_ALL)
csv_a.writerow(['bondlength'])
with open('joined.csv') as csvfile:
readCSV = csv.reader(csvfile, delimiter=',')
for row in readCSV:
print(row)
print(row[0])
f.close()
The matter is that you only read the first value of each line and write only a string in the new file.
In order to transpose the read lines, you can use the zip function.
I also delete the first open function which is useless because of the good use of with for opening the file.
Here the final code:
import csv
bondlength = []
with open("bond-dist-rep.csv") as csv_f:
read_csv = csv.reader(csv_f)
for row in read_csv:
bondlength.append(row)
# delete the header if you have one
bondlength.pop(0)
with open('joined.csv', 'w') as csvfile:
csv_a = csv.writer (csvfile, delimiter=',')
for transpose_row in zip(*bondlength):
csv_a.writerow(transpose_row)

create a new csv file in new subdirectory python 3.6

Been having trouble with using variables in a new dirpath when using with open to create a csv file.
I can create the dirpath fine along with the .csv filename and add them with os.path.join .
But when i try to use the entire correctly formatted path in the open statement it is adding an extra backslash next to the current backslashes in the string?? could not find any documentation on why this may be happening.
This is the error
FileNotFoundError: [Errno 2] No such file or directory: 'Logs\\14-05-2018\\dfg.csv'
If i simply write the following i can create the subfolders and csvs no problemo.
with open(Logs\1234\asd.csv) 'w') as csvfile:
So this is what i am getting an error in on line 43 which is the with open(csvlogPath, 'w') as csvfile: I have tried with r instead of 'w' and same problem. At a loss after two days time to ask you guys. :)
import csv, os.path
#Get and create csv filename string
logFN = input("Please name your trade.\n#")
suffix = '.csv'
csvname = logFN + suffix
#Create dir name string
t = time.strftime("%d-%m-%Y-%H%M")
dirsname = os.path.join('Logs', t)
csvlogPath = os.path.join(dirsname,csvname)
with open(csvlogPath, 'w') as csvfile:
filewriter = csv.writer(csvfile, delimiter=',', lineterminator='\n', quotechar='|', quoting=csv.QUOTE_MINIMAL)
filewriter.writerow(['get', 'new', 'values', 'later'])
with open(csvlogPath, 'w') as f:
reader = csv.reader(f)
# read file row by row
rwsCount = 0
for row in reader:
print (row, rwsCount)
rwsCount += 1
line_number = rwsCount-1
print (line_number)
with open(csvlogPath, 'w') as f:
mycsv = csv.reader(f)
mycsv = list(mycsv)
text = mycsv[line_number][0]
print (text)
you need to make the dirs in python you can use os.makedirs(path) like so:
csvlogPath = os.path.join(dirsname,csvname)
os.makedirs(os.path.dirname(csvlogPath), exist_ok=True)
with open(csvlogPath, 'w') as csvfile:
filewriter = csv.writer(csvfile, delimiter=',', lineterminator='\n', quotechar='|', quoting=csv.QUOTE_MINIMAL)
filewriter.writerow(['get', 'new', 'values', 'later'])
With open, use 'r' to read and 'w' to write so you need to change the next to opens to:
with open(csvlogPath, 'r') as f:
reader = csv.reader(f)
# read file row by row
rwsCount = 0
for row in reader:
print (row, rwsCount)
rwsCount += 1
line_number = rwsCount-1
print (line_number)
with open(csvlogPath, 'r') as f:
mycsv = csv.reader(f)
mycsv = list(mycsv)
text = mycsv[line_number][0]
test this code :
import csv, os.path
#Get and create csv filename string
import time
logFN = input("Please name your trade.\n#")
suffix = '.csv'
csvname = logFN + suffix
#Create dir name string
t = time.strftime("%d-%m-%Y-%H%M")
dirsname = os.path.join('Logs', t)
###########################
if not os.path.exists(dirsname):
os.makedirs(dirsname)
###########################
csvlogPath = os.path.join(dirsname,csvname)
with open(csvlogPath, 'w') as csvfile:
filewriter = csv.writer(csvfile, delimiter=',', lineterminator='\n', quotechar='|', quoting=csv.QUOTE_MINIMAL)
filewriter.writerow(['get', 'new', 'values', 'later'])
with open(csvlogPath, 'r') as f:
reader = csv.reader(f)
# read file row by row
rwsCount = 0
for row in reader:
print (row, rwsCount)
rwsCount += 1
line_number = rwsCount-1
print (line_number)
with open(csvlogPath, 'r') as f:
mycsv = csv.reader(f)
mycsv = list(mycsv)
text = mycsv[line_number][0]
print (text)

Read csv file auto delimeter

I have a small script that reads a pipe '|' delimited csv file and then writes it to another file as comma delimited. It works fine. Code, input file and output file below:
import csv
ifile = "d:\\python\\project\\cars-original.csv"
ofile = "d:\\python\\project\\cars.csv"
with open(ifile, 'r') as f:
reader = csv.reader(f, delimiter='|')
with open(ofile, 'w', newline='') as of:
writer = csv.writer(of, delimiter=',')
for row in reader:
writer.writerow(row)
Reading|Make|Model|Type|Value
Reading 0|Toyota|Previa|distance|19.83942
Reading 1|Dodge|Intrepid|distance|31.28257
Reading,Make,Model,Type,Value
Reading 0,Toyota,Previa,distance,19.83942
Reading 1,Dodge,Intrepid,distance,31.28257
I now want to modify the script so that it can auto-read the delimiter type.
I have found several examples online, but when I run mine I get a blank file for output. No errors, just blank. Not sure what I am doing wrong.
My modified (broken) script:
import csv
ifile = "d:\\python\\projects\\cars-original.csv"
ofile = "d:\\python\\projects\\cars.csv"
with open(ifile, 'r') as f:
reader = csv.reader(f)
dialect = csv.Sniffer().sniff(f.read(1024), delimiters=',|')
with open(ofile, 'w', newline='') as of:
writer = csv.writer(of, dialect)
for row in reader:
writer.writerow(row)
In the example in Python documentation (https://docs.python.org/3.6/library/csv.html) file pointer is moved to the beginning of the file, right after the dialect detection.
with open('example.csv', newline='') as csvfile:
dialect = csv.Sniffer().sniff(csvfile.read(1024))
csvfile.seek(0)
reader = csv.reader(csvfile, dialect)
This works:
import csv
ifile = "d:\\python\\project\\cars-original.csv"
ofile = "d:\\python\\project\\cars.csv"
with open(ifile, 'r') as f:
dialect = csv.Sniffer().sniff(f.readline(), [',', '|'])
f.seek(0)
reader = csv.reader(f, dialect)
with open(ofile, 'w', newline='') as of:
writer = csv.writer(of, delimiter=',')
for row in reader:
writer.writerow(row)

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