Path: csiph.com!fu-berlin.de!uni-berlin.de!not-for-mail
From: MRAB <python@mrabarnett.plus.com>
Newsgroups: comp.lang.python
Subject: Re: Howw to prevent the duplication of any value in a column within a CSV file (python)
Date: Tue, 26 Apr 2016 21:23:32 +0100
Lines: 34
Message-ID: <mailman.129.1461702225.32212.python-list@python.org>
References: <75e5d8dc-e15b-4350-95e8-490abd4aa14f@googlegroups.com> <531e2dda-c522-4b11-a030-f3f37078f344@googlegroups.com> <HE1PR07MB13561533B5D2DEE4B31F9AA9F0630@HE1PR07MB1356.eurprd07.prod.outlook.com> <CALwzidn=KRgvWZq9jc+G5hT6dxDOOjkYZLTbjLR6qNh82m2_LA@mail.gmail.com> <mailman.127.1461700361.32212.python-list@python.org> <49f4ffd8-d140-4f1b-95a9-75cb122e8b2f@googlegroups.com> <e442a9aa-60f2-641f-08fe-487ca1d29799@mrabarnett.plus.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Transfer-Encoding: 7bit
X-Trace: news.uni-berlin.de U7+gO9Yx7K/WvJBDzjUAiA19Ocry3SUip96/vhVvEE0A==
Return-Path: <python@mrabarnett.plus.com>
X-Original-To: python-list@python.org
Delivered-To: python-list@mail.python.org
X-Spam-Status: OK 0.001
X-Spam-Evidence: '*H*': 1.00; '*S*': 0.00; 'else:': 0.03; 'subject:file': 0.07; 'csv': 0.09; 'subject:CSV': 0.09; 'thread': 0.10; 'subject:python': 0.14; 'subject: \n ': 0.15; '2016': 0.16; 'adam': 0.16; 'file.close()': 0.16; 'found"': 0.16; 'from:addr:mrabarnett.plus.com': 0.16; 'from:addr:python': 0.16; 'from:name:mrab': 0.16; 'helps.': 0.16; 'ian.': 0.16; 'message- id:@mrabarnett.plus.com': 0.16; 'received:192.168.1.4': 0.16; 'received:io': 0.16; 'received:psf.io': 0.16; 'set()': 0.16; 'set:': 0.16; 'wrote:': 0.16; 'beginner': 0.18; 'example.': 0.18; 'noted': 0.22; 'header:In-Reply-To:1': 0.24; 'header:User- Agent:1': 0.26; 'checking': 0.27; '"no': 0.29; "i'm": 0.30; 'print': 0.30; 'tue,': 0.34; 'file': 0.34; 'except': 0.34; 'membership': 0.34; 'add': 0.34; 'could': 0.35; 'set.': 0.35; 'item': 0.35; 'but': 0.36; 'list,': 0.36; 'faster': 0.36; 'to:addr :python-list': 0.36; 'pm,': 0.36; 'subject:: ': 0.37; 'thanks': 0.37; 'subject:the': 0.39; "didn't": 0.39; 'received:192': 0.39; 'to:addr:python.org': 0.40; 'your': 0.60; 'hope': 0.61; 'skip:n 10': 0.62; 'elsewhere': 0.66; '26,': 0.72; 'subject:any': 0.84; 'subject:value': 0.84
X-CM-Score: 0.00
X-CNFS-Analysis: v=2.1 cv=K//fZHiI c=1 sm=1 tr=0 a=0nF1XD0wxitMEM03M9B4ZQ==:117 a=0nF1XD0wxitMEM03M9B4ZQ==:17 a=L9H7d07YOLsA:10 a=9cW_t1CCXrUA:10 a=s5jvgZ67dGcA:10 a=IkcTkHD0fZMA:10 a=q9EycRxEAAAA:8 a=dEy4AnFIG5xWnSMLpr4A:9 a=QEXdDO2ut3YA:10
X-AUTH: mrabarnett@:2500
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.0
In-Reply-To: <49f4ffd8-d140-4f1b-95a9-75cb122e8b2f@googlegroups.com>
X-BeenThere: python-list@python.org
X-Mailman-Version: 2.1.22
Precedence: list
List-Id: General discussion list for the Python programming language <python-list.python.org>
List-Unsubscribe: <https://mail.python.org/mailman/options/python-list>, <mailto:python-list-request@python.org?subject=unsubscribe>
List-Archive: <http://mail.python.org/pipermail/python-list/>
List-Post: <mailto:python-list@python.org>
List-Help: <mailto:python-list-request@python.org?subject=help>
List-Subscribe: <https://mail.python.org/mailman/listinfo/python-list>, <mailto:python-list-request@python.org?subject=subscribe>
X-Mailman-Original-Message-ID: <e442a9aa-60f2-641f-08fe-487ca1d29799@mrabarnett.plus.com>
X-Mailman-Original-References: <75e5d8dc-e15b-4350-95e8-490abd4aa14f@googlegroups.com> <531e2dda-c522-4b11-a030-f3f37078f344@googlegroups.com> <HE1PR07MB13561533B5D2DEE4B31F9AA9F0630@HE1PR07MB1356.eurprd07.prod.outlook.com> <CALwzidn=KRgvWZq9jc+G5hT6dxDOOjkYZLTbjLR6qNh82m2_LA@mail.gmail.com> <mailman.127.1461700361.32212.python-list@python.org> <49f4ffd8-d140-4f1b-95a9-75cb122e8b2f@googlegroups.com>
Xref: csiph.com comp.lang.python:107688

On 2016-04-26 21:07, Adam Davis wrote:
> On Tuesday, 26 April 2016 20:52:54 UTC+1, Ian  wrote:
>> On Tue, Apr 26, 2016 at 1:05 PM, Joaquin Alzola
>> <Joaquin.Alzola@lebara.com> wrote:
>> > Just an example. Didn't use the csv but just hope that it helps.
>> >
>> > name=[]
>> > name_exist="Dop"
>> >
>> > with open("dop.csv") as f:
>> >         for line in f:
>> >                 line_split=line.split(',')
>> >                 name.append(line_strip[0])
>> >         if name_exist in name:
>> >                 print "found name " + name_exist + " Can not append"
>> >         else:
>> >                 file = open("dop.csv",'a')
>> >                 print "No name found"
>> >                 file.write(name_exist)
>> > file.close()
>>
>> Except that as noted elsewhere in the thread a set would be a better
>> choice than a list, since checking membership is much faster on a set.
>
> Thanks for your help Ian. I'm a beginner right now, could you instruct me as to how I would create a set?
>
Create a set:

     the_set = set()

Add an item to a set:

     the_set.add(item)