I am using this code to find difference between two csv list and hove some formatting questions. This is probably an easy fix, but I am new and trying to learn and having alot of problems.
import difflib
diff=difflib.ndiff(open('test1.csv',"rb").readlines(), open('test2.csv',"rb").readlines())
try:
while 1:
print diff.next(),
except:
pass
the code works fine and I get the output I am looking for as:
Group,Symbol,Total
- Adam,apple,3850
? ^
+ Adam,apple,2850
? ^
bob,orange,-45
bob,lemon,66
bob,appl,-56
bob,,88
My question is how do I clean the formatting up, can I make the Group,Symbol,Total into sperate columns, and the line up the text below?
Also can i change the ? to represent a text I determine? such as test 1 and test 2 representing which sheet it comes from?
thanks for any help
Using difflib.unified_diff gives much cleaner output, see below.
Also, both difflib.ndiff and difflib.unified_diff return a Differ object that is a generator object, which you can directly use in a for loop, and that knows when to quit, so you don't have to handle exceptions yourself. N.B; The comma after line is to prevent print from adding another newline.
import difflib
s1 = ['Adam,apple,3850\n', 'bob,orange,-45\n', 'bob,lemon,66\n',
'bob,appl,-56\n', 'bob,,88\n']
s2 = ['Adam,apple,2850\n', 'bob,orange,-45\n', 'bob,lemon,66\n',
'bob,appl,-56\n', 'bob,,88\n']
for line in difflib.unified_diff(s1, s2, fromfile='test1.csv',
tofile='test2.csv'):
print line,
This gives:
--- test1.csv
+++ test2.csv
## -1,4 +1,4 ##
-Adam,apple,3850
+Adam,apple,2850
bob,orange,-45
bob,lemon,66
bob,appl,-56
So you can clearly see which lines were changed between test1.csv and test1.csv.
To line up the columns, you must use string formatting.
E.g. print "%-20s %-20s %-20s" % (row[0],row[1],row[2]).
To change the ? into any text test you like, you'd use s.replace('any text i like').
Your problem has more to do with the CSV format, since difflib has no idea it's looking at columnar fields. What you need is to figure out into which field the guide is pointing, so that you can adjust it when printing the columns.
If your CSV files are simple, i.e. they don't contain any quoted fields with embedded commas or (shudder) newlines, you can just use split(',') to separate them into fields, and figure out where the guide points as follows:
def align(line, guideline):
"""
Figure out which field the guide (^) points to, and the offset within it.
E.g., if the guide points 3 chars into field 2, return (2, 3)
"""
fields = line.split(',')
guide = guideline.index('^')
f = p = 0
while p + len(fields[f]) < guide:
p += len(fields[f]) + 1 # +1 for the comma
f += 1
offset = guide - p
return f, offset
Now it's easy to show the guide properly. Let's say you want to align your columns by printing everything 12 spaces wide:
diff=difflib.ndiff(...)
for line in diff:
code = line[0] # The diff prefix
print code,
if code == '?':
fld, offset = align(lastline, line[2:])
for f in range(fld):
print "%-12s" % '',
print ' '*offset + '^'
else:
fields = line[2:].rstrip('\r\n').split(',')
for f in fields:
print "%-12s" % f,
print
lastline = line[2:]
Be warned that the only reliable way to parse CSV files is to use the csv module (or a robust alternative); but getting it to play well with the diff format (in full generality) would be a bit of a headache. If you're mainly interested in readability and your CSV isn't too gnarly, you can probably live with an occasional mix-up.
Related
I am fairly new to Python and need a little help here.
I have a Python script running on Python 2.6 that parses some JSON.
Example Code:
if "prid" in data[p]["prdts"][n]:
print data[p]["products"][n]["prid"],
if "metrics" in data[p]["prdts"][n]:
lenmet = len(data[p]["prdts"][n]["metrics"])
i = 0
while (i < lenmet):
if (data[p]["prdts"][n]["metrics"][i]["metricId"] == "price"):
print data[p]["prdts"][n]["metrics"][i]["metricValue"]["value"]
break
Now, this prints values in 2 columns:
prid price
123 20
234 40
As you see the fields separator above is ' '. How can I put a field separator like BEL character in the output?
Sample expected output:
prid price
123^G20
234^G40
FWIW, your while loop doesn't increment i, so it will loop forever, but I assume that was just a copy & paste error, and I'll ignore it in the rest of my answer.
If you want to use two separate print statements to print your data on one line you can't avoid getting that space produced by the first print statement. Instead, simply save the prid data until you can print it with the price in one go using string concatenation. Eg,
if "prid" in data[p]["prdts"][n]:
prid = [data[p]["products"][n]["prid"]]
if "metrics" in data[p]["prdts"][n]:
lenmet = len(data[p]["prdts"][n]["metrics"])
i = 0
while (i < lenmet):
if (data[p]["prdts"][n]["metrics"][i]["metricId"] == "price"):
price = data[p]["prdts"][n]["metrics"][i]["metricValue"]["value"]
print str(prid) + '\a' + str(price)
break
Note that I'm explicitly converting the prid and price to string. Obviously, if either of those items is already a string then you don't need to wrap it in str(). Normally, we can let print convert objects to string for us, but we can't do
print prid, '\a', price
here because that will give us an unwanted space between each item.
Another approach is to make use of the new print() function, which we can import using a __future__ import at the top of the script, before other imports:
from __future__ import print_function
# ...
if "prid" in data[p]["prdts"][n]:
print(data[p]["products"][n]["prid"], end='\a')
if "metrics" in data[p]["prdts"][n]:
lenmet = len(data[p]["prdts"][n]["metrics"])
i = 0
while (i < lenmet):
if (data[p]["prdts"][n]["metrics"][i]["metricId"] == "price"):
print(data[p]["prdts"][n]["metrics"][i]["metricValue"]["value"])
break
I don't understand why you want to use BEL as a separator rather than something more conventional, eg TAB. The BEL char may print as ^G in your terminal, but it's invisible in mine, and if you save this output to a text file it may not display correctly in a text viewer / editor.
BTW, It would have been better if you posted a Minimal, Complete, Verifiable Example that focuses on your actual printing problem, rather than all that crazy JSON parsing stuff, which just makes your question look more complicated than it really is, and makes it impossible to test your code or their modifications to it.
I'm trying to edit a CSV file using informations from a first one. That doesn't seem simple to me as I should filter multiple things. Let's explain my problem.
I have two CSV files, let's say patch.csv and origin.csv. Output csv file should have the same pattern as origin.csv, but with corrected values.
I want to replace trip_headsign column fields in origin.csv using forward_line_name column in patch.csv if direction_id field in origin.csv row is 0, or using backward_line_name if direction_id is 1.
I want to do this only if the part of the line_id value in patch.csv between ":" and ":" symbols is the same as the part of route_id value in origin.csv before the ":" symbol.
I know how to replace a whole line, but not only some parts, especially that I sometimes have to look only part of a value.
Here is a sample of origin.csv:
route_id,service_id,trip_id,trip_headsign,direction_id,block_id
210210109:001,2913,70405957139549,70405957,0,
210210109:001,2916,70405961139553,70405961,1,
and a sample of patch.csv:
line_id,line_code,line_name,forward_line_name,forward_direction,backward_line_name,backward_direction,line_color,line_sort,network_id,commercial_mode_id,contributor_id,geometry_id,line_opening_time,line_closing_time
OIF:100110010:10OIF439,10,Boulogne Pont de Saint-Cloud - Gare d'Austerlitz,BOULOGNE / PONT DE ST CLOUD - GARE D'AUSTERLITZ,OIF:SA:8754700,GARE D'AUSTERLITZ - BOULOGNE / PONT DE ST CLOUD,OIF:SA:59400,DFB039,91,OIF:439,metro,OIF,geometry:line:100110010:10,05:30:00,25:47:00
OIF:210210109:001OIF30,001,FFOURCHES LONGUEVILLE PROVINS,Place Mérot - GARE DE LONGUEVILLE,,GARE DE LONGUEVILLE - Place Mérot,OIF:SA:63:49,000000 1,OIF:30,bus,OIF,,05:39:00,19:50:00
Each file has hundred of lines I need to parse and edit this way.
Separator is comma in my csv files.
Based on mhopeng answer to a previous question, I obtained that code:
#!/usr/bin/env python2
from __future__ import print_function
import fileinput
import sys
# first get the route info from patch.csv
f = open(sys.argv[1])
d = open(sys.argv[2])
# ignore header line
#line1 = f.readline()
#line2 = d.readline()
# get line of data
for line1 in f.readline():
line1 = f.readline().split(',')
route_id = line1[0].split(':')[1] # '210210109'
route_forward = line1[3]
route_backward = line1[5]
line_code = line1[1]
# process origin.csv and replace lines in-place
for line in fileinput.input(sys.argv[2], inplace=1):
line2 = d.readline().split(',')
num_route = line2[0].split(':')[0]
# prevent lines with same route_id but different line_code to be considered as the same line
if line.startswith(route_id) and (num_route == line_code):
if line.startswith(route_id):
newline = line.split(',')
if newline[4] == 0:
newline[3] = route_backward
else:
newline[3] = route_forward
print('\t'.join(newline),end="")
else:
print(line,end="")
But unfortunately, that doesn't push the right forward or backward_line_name in trip_headsign (always forward is used), the condition to compare patch.csv line_code to the end of route_id of origin.csv (after the ":") doesn't work, and the script finally triggers that error, before finishing parsing the file:
Traceback (most recent call last):
File "./GTFS_enhancer_headsigns.py", line 28, in
if newline[4] == 0:
IndexError: list index out of range
Could you please help me fixing these three problems?
Thanks for your help :)
You really should consider using the python csv module instead of split().
Out of experience , everything is much easier when working with csv files and the csv module.
This way you can iterate through the dataset in a structured way without the risk of getting index out of range errors.
What I'm trying to do is open a file, then find every instance of '[\x06I"' and '\x06;', then return whatever is between the two.
Since this is not a standard text file (it's map data from RPG maker) readline() will not work for my purposes, as the file is not at all formatted in such a way that the data I want is always neatly within one line by itself.
What I'm doing right now is loading the file into a list with read(), then simply deleting characters from the very beginning until I hit the string '[\x06I'. Then I scan ahead to find '\x06;', store what's between them as a string, append said string to a list, then resume at the character after the semicolon I found.
It works, and I ended up with pretty much exactly what I wanted, but I feel like that's the worst possible way to go about it. Is there a more efficient way?
My relevant code:
while eofget == 0:
savor = 0
while savor == 0 or eofget == 0:
if line[0:4] == '[\x06I"':
x = 4
spork = 0
while spork == 0:
x += 1
if line[x] == '\x06':
if line[x+1] == ';':
spork = x
savor = line[5:spork] + "\n"
line = line[x+1:]
linefinal[lineinc] = savor
lineinc += 1
elif line[x:x+7] == '#widthi':
print("eof reached")
spork = 1
eofget = 1
savor = 0
elif line[x:x+7] == '#widthi':
print("finished map " + mapname)
eofget = 1
savor = 0
break
else:
line = line[1:]
You can just ignore the variable names. I just name things the first thing that comes to mind when I'm doing one-offs like this. And yes, I am aware a few things in there don't make any sense, but I'm saving cleanup for when I finalize the code.
When eofget gets flipped on this subroutine terminates and the next map is loaded. Then it repeats. The '#widthi' check is basically there to save time, since it's present in every map and indicates the beginning of the map data, AKA data I don't care about.
I feel this is a natural case to use regular expressions. Using the findall method:
>>> s = 'testing[\x06I"text in between 1\x06;filler text[\x06I"text in between 2\x06;more filler[\x06I"text in between \n with some line breaks \n included in the text\x06;ending'
>>> import re
>>> p = re.compile('\[\x06I"(.+?)\x06;', re.DOTALL)
>>> print(p.findall(s))
['text in between 1', 'text in between 2', 'text in between \n with some line breaks \n included in the text']
The regex string '\[\x06I"(.+?)\x06;'can be interpreted as follows:
Match as little as possible (denoted by ?) of an undetermined number of unspecified characters (denoted by .+) surrounded by '[\x06I"' and '\x06;', and only return the enclosed text (denoted by the parentheses around .+?)
Adding re.DOTALL in the compile makes the .? match line breaks as well, allowing multi-line text to be captured.
I would use split():
fulltext = 'adsfasgaseg[\x06I"thisiswhatyouneed\x06;sdfaesgaegegaadsf[\x06I"this is the second what you need \x06;asdfeagaeef'
parts = fulltext.split('[\x06I"') # split by first label
results = []
for part in parts:
if '\x06;' in part: # if second label exists in part
results.append(part.split('\x06;')[0]) # get the part until the second label
print results
I have recently been learning some Python and how to apply it to my work. I have written a couple of scripts successfully, but I am having an issue I just cannot figure out.
I am opening a file with ~4000 lines, two tab separated columns per line. When reading the input file, I get an index error saying that the list index is out of range. However, while I get the error every time, it doesn't happen on the same line every time (as in, it will throw the error on different lines everytime!). So, for some reason, it works generally but then (seemingly) randomly fails.
As I literally only started learning Python last week, I am stumped. I have looked around for the same problem, but not found anything similar. Furthermore I don't know if this is a problem that is language specific or IPython specific. Any help would be greatly appreciated!
input = open("count.txt", "r")
changelist = []
listtosort = []
second = str()
output = open("output.txt", "w")
for each in input:
splits = each.split("\t")
changelist = list(splits[0])
second = int(splits[1])
print second
if changelist[7] == ";":
changelist.insert(6, "000")
va = "".join(changelist)
var = va + ("\t") + str(second)
listtosort.append(var)
output.write(var)
elif changelist[8] == ";":
changelist.insert(6, "00")
va = "".join(changelist)
var = va + ("\t") + str(second)
listtosort.append(var)
output.write(var)
elif changelist[9] == ";":
changelist.insert(6, "0")
va = "".join(changelist)
var = va + ("\t") + str(second)
listtosort.append(var)
output.write(var)
else:
#output.write(str("".join(changelist)))
va = "".join(changelist)
var = va + ("\t") + str(second)
listtosort.append(var)
output.write(var)
output.close()
The error
---------------------------------------------------------------------------
IndexError Traceback (most recent call last)
/home/a/Desktop/sharedfolder/ipytest/individ.ins.count.test/<ipython-input-87-32f9b0a1951b> in <module>()
57 splits = each.split("\t")
58 changelist = list(splits[0])
---> 59 second = int(splits[1])
60
61 print second
IndexError: list index out of range
Input:
ID=cds0;Name=NP_414542.1;Parent=gene0;Dbxref=ASAP:ABE-0000006,UniProtKB%2FSwiss-Prot:P0AD86,Genbank:NP_414542.1,EcoGene:EG11277,GeneID:944742;gbkey=CDS;product=thr 12
ID=cds1000;Name=NP_415538.1;Parent=gene1035;Dbxref=ASAP:ABE-0003451,UniProtKB%2FSwiss-Prot:P31545,Genbank:NP_415538.1,EcoGene:EG11735,GeneID:946500;gbkey=CDS;product=deferrrochelatase%2C 50
ID=cds1001;Name=NP_415539.1;Parent=gene1036;Note=PhoB-dependent%2C 36
Desired output:
ID=cds0000;Name=NP_414542.1;Parent=gene0;Dbxref=ASAP:ABE-0000006,UniProtKB%2FSwiss-Prot:P0AD86,Genbank:NP_414542.1,EcoGene:EG11277,GeneID:944742;gbkey=CDS;product=thr 12
ID=cds1000;Name=NP_415538.1;Parent=gene1035;Dbxref=ASAP:ABE-0003451,UniProtKB%2FSwiss-Prot:P31545,Genbank:NP_415538.1,EcoGene:EG11735,GeneID:946500;gbkey=CDS;product=deferrrochelatase%2C 50
ID=cds1001;Name=NP_415539.1;Parent=gene1036;Note=PhoB-dependent%2C 36
The reason you're getting the IndexError is that your input-file is apparently not entirely tab delimited. That's why there is nothing at splits[1] when you attempt to access it.
Your code could use some refactoring. First of all you're repeating yourself with the if-checks, it's unnecessary. This just pads the cds0 to 7 characters which is probably not what you want. I threw the following together to demonstrate how you could refactor your code to be a little more pythonic and dry. I can't guarantee it'll work with your dataset, but I'm hoping it might help you understand how to do things differently.
to_sort = []
# We can open two files using the with statement. This will also handle
# closing the files for us, when we exit the block.
with open("count.txt", "r") as inp, open("output.txt", "w") as out:
for each in inp:
# Split at ';'... So you won't have to worry about whether or not
# the file is tab delimited
changed = each.split(";")
# Get the value you want. This is called unpacking.
# The value before '=' will always be 'ID', so we don't really care about it.
# _ is generally used as a variable name when the value is discarded.
_, value = changed[0].split("=")
# 0-pad the desired value to 7 characters. Python string formatting
# makes this very easy. This will replace the current value in the list.
changed[0] = "ID={:0<7}".format(value)
# Join the changed-list with the original separator and
# and append it to the sort list.
to_sort.append(";".join(changed))
# Write the results to the file all at once. Your test data already
# provided the newlines, you can just write it out as it is.
output.writelines(to_sort)
# Do what else you need to do. Maybe to_list.sort()?
You'll notice that this code is reduces your code down to 8 lines but achieves the exact same thing, does not repeat itself and is pretty easy to understand.
Please read the PEP8, the Zen of python, and go through the official tutorial.
This happens when there is a line in count.txt which doesn't contain the tab character. So when you split by tab character there will not be any splits[1]. Hence the error "Index out of range".
To know which line is causing the error, just add a print(each) after splits in line 57. The line printed before the error message is your culprit. If your input file keeps changing, then you will get different locations. Change your script to handle such malformed lines.
I have a tab delimited text file with the following data:
ahi1
b/se
ahi
test -2.435953
1.218364
ahi2
b/se
ahi
test -2.001858
1.303935
I want to extract the two floating point numbers to a separate csv file with two columns, ie.
-2.435953 1.218264
-2.001858 1.303935
Currently my hack attempt is:
import csv
from itertools import islice
results = csv.reader(open('test', 'r'), delimiter="\n")
list(islice(results,3))
print results.next()
print results.next()
list(islice(results,3))
print results.next()
print results.next()
Which is not ideal. I am a Noob to Python so I apologise in advance and thank you for your time.
Here is the code to do the job:
import re
# this is the same data just copy/pasted from your question
data = """ ahi1
b/se
ahi
test -2.435953
1.218364
ahi2
b/se
ahi
test -2.001858
1.303935"""
# what we're gonna do, is search through it line-by-line
# and parse out the numbers, using regular expressions
# what this basically does is, look for any number of characters
# that aren't digits or '-' [^-\d] ^ means NOT
# then look for 0 or 1 dashes ('-') followed by one or more decimals
# and a dot and decimals again: [\-]{0,1}\d+\.\d+
# and then the same as first..
pattern = re.compile(r"[^-\d]*([\-]{0,1}\d+\.\d+)[^-\d]*")
results = []
for line in data.split("\n"):
match = pattern.match(line)
if match:
results.append(match.groups()[0])
pairs = []
i = 0
end = len(results)
while i < end - 1:
pairs.append((results[i], results[i+1]))
i += 2
for p in pairs:
print "%s, %s" % (p[0], p[1])
The output:
>>>
-2.435953, 1.218364
-2.001858, 1.303935
Instead of printing out the numbers, you could save them in a list and zip them together afterwards..
I'm using the python regular expression framework to parse the text. I can only recommend you pick up regular expressions if you don't already know it. I find it very useful to parse through text and all sorts of machine generated output-files.
EDIT:
Oh and BTW, if you're worried about the performance, I tested on my slow old 2ghz IBM T60 laptop and I can parse a megabyte in about 200ms using the regex.
UPDATE:
I felt kind, so I did the last step for you :P
Maybe this can help
zip(*[results]*5)
eg
import csv
from itertools import izip
results = csv.reader(open('test', 'r'), delimiter="\t")
for result1, result2 in (x[3:5] for x in izip(*[results]*5)):
... # do something with the result
Tricky enough but more eloquent and sequential solution:
$ grep -v "ahi" myFileName | grep -v se | tr -d "test\" " | awk 'NR%2{printf $0", ";next;}1'
-2.435953, 1.218364
-2.001858, 1.303935
How it works: Basically remove specific text lines, then remove unwanted text in lines, then join every second line with formatting. I just added the comma for beautification purposes. Leave the comma out of awks printf ", " if you don't need it.