Using C/C++ : How can I sort a specific column from a CSV file. Assuming that CS
ID: 3928921 • Letter: U
Question
Using C/C++ :
How can I sort a specific column from a CSV file. Assuming that CSV file has large data set (~9000) on each column.I want to read from one specific column (5th Column) and sort (Bubble or insertion sort) them in descending order. And time it (find the running time of the program). Then, Create a program that will, in turn, run multiple processes “concurrently” using “fork( )” and “exec( )”. Do the sort, again, in parallel for 2 concurrent processes, then 4, and 10 processes. Now time this sort again.
How will you pass data (parts of the array) to each process (IPC)? (Files, pipes, shared memory, message queues?)
Explanation / Answer
#include <stdio.h>
#include <stdlib.h>
import csv
import itertoolsfrom itertools import groupby as gb
reader = csv.DictReader(open('Full_List.csv', 'r'))
groups = gb(reader, lambda d: d['red label'])
result = [max(g, key=lambda d: d['red label'])
for k, g in groups]
writer = csv.DictWriter(open('output.csv', 'w'), reader.fieldnames)
writer.writeheader()
writer.writerows(result)
import pandas as pd
df = pd.read_csv('Full_List.csv')
df = df.sort('red label')
df.to_csv('Full_List_sorted.csv', index=False)
import csv
reader = csv.DictReader(open('Full_List.csv', 'r'))
result = sorted(reader, key=lambda d: float(d['red label']))
writer = csv.DictWriter(open('output.csv', 'w'), reader.fieldnames)
writer.writeheader() writer.writerows(result)
reader = cvs.DictReader(ifile)
print 'Try the float version' sortedlist = sorted(reader, key = lambda d:
float(d[options.statistic]),
reverse=options.high)
except ValueError:
print 'Need to use the text version' ifile.seek(0) ifile.next() sortedlist = sorted(reader, key=lambda d:
d[options.statistic], reverse=options.high)
.close()
ofile = open(options.fileout, 'wb')
writer = csv.DictWriter(ofile, fieldnames=outfields, extrasactions='ignore', restval = '')
writer.writerow(dict((fn, fn) for fn in outfields))
writer.writerows(sortedlist)
ofile.close()