1) CSV format cleaning and conversion
description
The attachment is a CSV format file, and the extracted data is converted into the following format:
( 1) Sort in reverse order by line;
( 2) Each row of data is arranged in reverse order;
( 3) a semicolon (;) instead of a comma (,) divided data, no empty cells.
The data will be output after conversion according to the above requirements.
Input and output examples
The following is a sample format, not the final result.
|
|
Input |
Output |
| Example 1 |
(The following is in the file) 1,2,3 4,5,6 7,8,9 |
9;8;7 6;5;4 3;2;1 |
fo = open ("data.csv")
lt = fo.readlines () # an element in the list lt
lt = lt [::-1] # reverse order
for item in lt:
item = item.strip (' \ n ')
#Remove the newline at the end of each line
item = item [::-1] #Reverse the order of each line element item = item.replace ("", "") #Remove the space of each line element
item = item .split (',') #According to split each line of elements to form a list
print (';'. join (item))
#Split the elements in the list item; split to form a long string fo.close () #Note
: Use the strip () method to remove the carriage return at the end of each line, and use replace () to remove the spaces on both sides of each line element.
2) CSV format column transformation
description
The attachment is a CSV file, please arrange each row in reverse order after column output, without changing the format of each element (such as the layout of surrounding spaces, etc.).
Input and output examples
This is a format example, not the correct result.
|
|
Input |
Output |
| Example 1 |
(The following is the content of the file) 1,2,3,4 a,b,c,d |
4,3,2,1 d,c,b,a |
How to read attachments in the attachment program?
Attachment 1: data.csv
#My answer fo = open ("data.csv")
lt = fo.readlines () #Return list lt
for item in lt:
item = item.strip ('\ n')
item = item.split (',' )
item = item [::-1]
print (','. join (item))
fo.close () #Reference
answer
f = open ("data.csv")
for line in f: #Directly on the text file f Iterate through
line = line.strip ("\ n")
ls = line.split (",")
ls = ls [::-1]
print (",". Join (ls))
f.close ()
3) CSV format data cleaning
description
The attachment is a CSV file, there are spaces before and after each data, please clean it, the requirements are as follows:
( 1) Remove the space before and after each data, that is, the data is only separated by a comma (,);
( 2) Printout after cleaning.
Input and output examples
Here is a format example, not the correct result.
|
|
Input |
Output |
| Example 1 |
(In the file) 1, 2, 3, 4, 5 'a', 'b' , 'c' , 'd','e' |
1,2,3,4,5 'a','b','c','d','e' |
How to read attachments in the attachment program?
Attachment 1: data.csv
#My answer fo = open ("data.csv")
lt = fo.readlines ()
for item in lt: #Line by line processing, suitable for large files (a dozen G levels)
item = item.strip ('\ n ')
item = item.replace ("", "")
item = item.split (', ')
print (', '. join (item))
#Reference
answer f = open ("data.csv")
s = f.read () #Read all content
s = s.replace ("", "") #Replace all spaces at once, suitable for small files
print (s)
f.close ()