I wrote the following code to split my data matrix into a csv file:
f = open('midi_data.csv', 'w', newline="")
writer = csv.writer(f, delimiter= ',',quotechar =',',quoting=csv.QUOTE_MINIMAL)
for item in data:
writer.writerow(item)
print(item)
f.close()
But the csv file ends up looking like this:
tuples not separated by columns but by commas in one column only
What am I doing wrong?
The data seems to be written correctly inside the tuples, because when running the code it outputs the following:
enter image description here
Related
i am searching everywhere for a method to write a list of floats into csv but must be in column format.
My code for writing csv as follow:
csvfile=open('Test.csv','w', newline='')
obj=csv.writer(csvfile)
obj.writerow(list_dis_B1_avg)
csvfile.close()
It turn out that the floats are written in rows.
I have a list of floats stored under "list_dis_B1_avg"
How can i just write it in column?
You dont need any csv module to do that:
with open("Test.csv", "w") as f: # use with to close the file in any case
f.write("\n".join(list_dis_B1_avg)) # newline between the elements
More about the with keyword: https://www.geeksforgeeks.org/with-statement-in-python/
More about str.join(): https://www.programiz.com/python-programming/methods/string/join
I have a list of dictionaries
d = [{'value':'foo_1', 'word_list':['blah1', 'blah2']}, ...., {'value': 'foo_n', 'word_list':['meh1', 'meh2']}]
I want to write this to a CSV file with all the 'value' keys in one column, and then each individual word from the "value"'s word_list as its own column. So I have the first row as
foo_1 blah_1 blah_2
and so on.
I don't know how many dictionaries I have, or how many words I have in "word_list".
How would I go about doing this in Python 3?
Thanks!
I figured out a solution, but it's kind of messy (wow, I can't write a bit of code without it being in the "proper format"...how annoying):
with open('filename', 'w') as f:
for key in d.keys():
f.write("%s,"%(key))
for word in d[key]:
f.write("%s,"%(word))
f.write("\n")
You can loop through the dictionaries one at a time, construct the list and then use the csv module to write the data as I have shown here
import csv
d = [{'value':'foo_1', 'word_list':['blah1', 'blah2']}, {'value': 'foo_n', 'word_list':['meh1', 'meh2']}]
with open('test_file.csv', 'w') as file:
writer = csv.writer(file)
for val_dict in d:
csv_row = [val_dict['value']] + val_dict['word_list']
writer.writerow(csv_row)
It should work for word lists of arbitrary length and as many dictionaries as you want.
It would probably be easiest to flatten each row into a normal list before writing it to the file. Something like this:
with open(filename, 'w') as file:
writer = csv.writer(file)
for row in data:
out_row = [row['value']]
for word in row['word_list']:
out_row.append(word)
csv.writerow(out_row)
# Shorter alternative to the two loops:
# csv.writerow((row['value'], *row['word_list']) for row in data)
I am trying something similar-
sample={"name":["age","number","email"]}
#dictionary stores the relevant data in above format
with open('selected.csv','w') as csvf:
[csvf.write('{0},{1}\n'.format(key,value)) for key,value in
sample.items()]
#writing data in a csv file with my formatting
"Aaron",[21,020303030,"Aaron#blahblah.com"]
#csv file sample entry
Everything works fine but CSV file shows List brackets, how can I remove them?
This isn't difficult if you use the standard library csv module:
import csv
sample={"name":["age","number","email"]}
with open('selected.csv', 'w+', newline='') as csvf:
writer = csv.writer(csvf)
for k, v in sample.items():
writer.writerow([k, *v]) # unpack v into a list with k
This would produce a file with one line:
name,age,number,email
I am trying read a CSV file into python 3 using unicodecsv library. Code follows :
with open('filename.csv', 'rb') as f:
reader = unicodecsv.DictReader(f)
Student_Data = list(reader)
But the order of the columns in the CSV file is not retained when I output any element from the Student_Data. The output contains any random order of the columns. Is there anything wrong with the code? How do I fix this?
As stated in csv.DictReader documentation, the DictReader object behaves like a dict - so it is not ordered.
You can obtain the list of the fieldnames with:
reader.fieldnames
But if you only want to obtain a list of the field values, in original order, you can just use a normal reader:
with open('filename.csv', 'rb') as f:
reader = unicodecsv.reader(f)
for row in reader:
Student_Data = row
I have a large data file like this
Words
One
Two
Three
....
Threethousand
I am trying to print this list to a text file with this code:
df1 = df[['Words']]
with open('atextfile.txt', 'w', encoding='utf-8') as outfile:
print(df1, file=outfile)
But what happens is that it doesn't print out the whole DF, it ends up looking like this:
Words
One
Two
Three
....
Threethousand
Fourthousand
Fivethousand
How can I print out the whole DF?
I would use to_string to do this, it doesn't abbreviate like the printing:
df['Words'].to_string('atextfile.txt')
# or
df[['Words']].to_string('atextfile.txt')