How to read one character from a file as a key into a dictionary, then make the next n characters its value?












-1














Lets say we have a .txt file like so (all on one line):



A2.)43@|@C3::#


So we want "A" as key for the value ".)" and "4" as key for the value "@|@" etc.. The number after the key tells us how many characters to read as the value, and the character after is the key for the next item in the dictionary.



The thing I'm struggling with is writing the loop. I'm thinking that we might want to iterate over the length of the file using a for loop. But I don't really know how to proceed.






python file dictionary file-read







share|improve this question




















  • 1




    A while loop would be better so you can increment the index variable arbitrarily (or check for end of file instead) to process all characters of a value at once.
    – Michael Butscher
    Nov 12 at 22:31












  • Here's a hint: go to class and read your notes.
    – Julien
    Nov 12 at 22:34










  • Why would the "3" character following the "4" be skipped?
    – martineau
    Nov 12 at 23:21
















-1














Lets say we have a .txt file like so (all on one line):



A2.)43@|@C3::#


So we want "A" as key for the value ".)" and "4" as key for the value "@|@" etc.. The number after the key tells us how many characters to read as the value, and the character after is the key for the next item in the dictionary.



The thing I'm struggling with is writing the loop. I'm thinking that we might want to iterate over the length of the file using a for loop. But I don't really know how to proceed.






python file dictionary file-read







share|improve this question




















  • 1




    A while loop would be better so you can increment the index variable arbitrarily (or check for end of file instead) to process all characters of a value at once.
    – Michael Butscher
    Nov 12 at 22:31












  • Here's a hint: go to class and read your notes.
    – Julien
    Nov 12 at 22:34










  • Why would the "3" character following the "4" be skipped?
    – martineau
    Nov 12 at 23:21














-1












-1








-1







Lets say we have a .txt file like so (all on one line):



A2.)43@|@C3::#


So we want "A" as key for the value ".)" and "4" as key for the value "@|@" etc.. The number after the key tells us how many characters to read as the value, and the character after is the key for the next item in the dictionary.



The thing I'm struggling with is writing the loop. I'm thinking that we might want to iterate over the length of the file using a for loop. But I don't really know how to proceed.






python file dictionary file-read







share|improve this question















Lets say we have a .txt file like so (all on one line):



A2.)43@|@C3::#


So we want "A" as key for the value ".)" and "4" as key for the value "@|@" etc.. The number after the key tells us how many characters to read as the value, and the character after is the key for the next item in the dictionary.



The thing I'm struggling with is writing the loop. I'm thinking that we might want to iterate over the length of the file using a for loop. But I don't really know how to proceed.






python file dictionary file-read




python file dictionary file-read






share|improve this question















share|improve this question













share|improve this question




share|improve this question








edited Nov 12 at 23:18









martineau

65.5k988177




65.5k988177










asked Nov 12 at 22:28









bullebullebagarn

162




162








  • 1




    A while loop would be better so you can increment the index variable arbitrarily (or check for end of file instead) to process all characters of a value at once.
    – Michael Butscher
    Nov 12 at 22:31












  • Here's a hint: go to class and read your notes.
    – Julien
    Nov 12 at 22:34










  • Why would the "3" character following the "4" be skipped?
    – martineau
    Nov 12 at 23:21














  • 1




    A while loop would be better so you can increment the index variable arbitrarily (or check for end of file instead) to process all characters of a value at once.
    – Michael Butscher
    Nov 12 at 22:31












  • Here's a hint: go to class and read your notes.
    – Julien
    Nov 12 at 22:34










  • Why would the "3" character following the "4" be skipped?
    – martineau
    Nov 12 at 23:21








1




1




A while loop would be better so you can increment the index variable arbitrarily (or check for end of file instead) to process all characters of a value at once.
– Michael Butscher
Nov 12 at 22:31






A while loop would be better so you can increment the index variable arbitrarily (or check for end of file instead) to process all characters of a value at once.
– Michael Butscher
Nov 12 at 22:31














Here's a hint: go to class and read your notes.
– Julien
Nov 12 at 22:34




Here's a hint: go to class and read your notes.
– Julien
Nov 12 at 22:34












Why would the "3" character following the "4" be skipped?
– martineau
Nov 12 at 23:21




Why would the "3" character following the "4" be skipped?
– martineau
Nov 12 at 23:21












1 Answer
1






active

oldest

votes


















0














This worked for me



stringText = "A2.)43@|@C3::#"





i=0

myDictionary = {}





while True:

    try:

        #First we grab the key character using i

        keyCharacter = stringText[i]



        #Then we grab the next character which will tell us how many characters they value will have

        # We also convert it to integer for future use

        valueLength = int(stringText[i+1])



        #Then we grab the value by slicing the string

        valueCharacters = stringText[i+2:i+2+valueLength]



        #We add this to the dictionary

        myDictionary[keyCharacter] = valueCharacters



        #We update i to continue where we left off

        i = i+2+valueLength





    except IndexError:

        break



print myDictionary


Instead of the "try and except" you could also see how long that string is and do and if statement to break the loop when i is bigger than the length of the string.






share|improve this answer





















    Your Answer






    StackExchange.ifUsing("editor", function () {
    StackExchange.using("externalEditor", function () {
    StackExchange.using("snippets", function () {
    StackExchange.snippets.init();
    });
    });
    }, "code-snippets");

    StackExchange.ready(function() {
    var channelOptions = {
    tags: "".split(" "),
    id: "1"
    };
    initTagRenderer("".split(" "), "".split(" "), channelOptions);

    StackExchange.using("externalEditor", function() {
    // Have to fire editor after snippets, if snippets enabled
    if (StackExchange.settings.snippets.snippetsEnabled) {
    StackExchange.using("snippets", function() {
    createEditor();
    });
    }
    else {
    createEditor();
    }
    });

    function createEditor() {
    StackExchange.prepareEditor({
    heartbeatType: 'answer',
    autoActivateHeartbeat: false,
    convertImagesToLinks: true,
    noModals: true,
    showLowRepImageUploadWarning: true,
    reputationToPostImages: 10,
    bindNavPrevention: true,
    postfix: "",
    imageUploader: {
    brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
    contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
    allowUrls: true
    },
    onDemand: true,
    discardSelector: ".discard-answer"
    ,immediatelyShowMarkdownHelp:true
    });


    }
    });














    draft saved

    draft discarded


















    StackExchange.ready(
    function () {
    StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53271009%2fhow-to-read-one-character-from-a-file-as-a-key-into-a-dictionary-then-make-the%23new-answer', 'question_page');
    }
    );

    Post as a guest















    Required, but never shown

























    1 Answer
    1






    active

    oldest

    votes








    1 Answer
    1






    active

    oldest

    votes









    active

    oldest

    votes






    active

    oldest

    votes









    0














    This worked for me



    stringText = "A2.)43@|@C3::#"
    

    

    
i=0
    
myDictionary = {}
    

    

    
while True:
    
    try:
    
        #First we grab the key character using i
    
        keyCharacter = stringText[i]
    

    
        #Then we grab the next character which will tell us how many characters they value will have
    
        # We also convert it to integer for future use
    
        valueLength = int(stringText[i+1])
    

    
        #Then we grab the value by slicing the string
    
        valueCharacters = stringText[i+2:i+2+valueLength]
    

    
        #We add this to the dictionary
    
        myDictionary[keyCharacter] = valueCharacters
    

    
        #We update i to continue where we left off
    
        i = i+2+valueLength
    

    

    
    except IndexError:
    
        break
    

    
print myDictionary


    Instead of the "try and except" you could also see how long that string is and do and if statement to break the loop when i is bigger than the length of the string.






    share|improve this answer


























      0














      This worked for me



      stringText = "A2.)43@|@C3::#"
      

      

      
i=0
      
myDictionary = {}
      

      

      
while True:
      
    try:
      
        #First we grab the key character using i
      
        keyCharacter = stringText[i]
      

      
        #Then we grab the next character which will tell us how many characters they value will have
      
        # We also convert it to integer for future use
      
        valueLength = int(stringText[i+1])
      

      
        #Then we grab the value by slicing the string
      
        valueCharacters = stringText[i+2:i+2+valueLength]
      

      
        #We add this to the dictionary
      
        myDictionary[keyCharacter] = valueCharacters
      

      
        #We update i to continue where we left off
      
        i = i+2+valueLength
      

      

      
    except IndexError:
      
        break
      

      
print myDictionary


      Instead of the "try and except" you could also see how long that string is and do and if statement to break the loop when i is bigger than the length of the string.






      share|improve this answer
























        0












        0








        0






        This worked for me



        stringText = "A2.)43@|@C3::#"
        

        

        
i=0
        
myDictionary = {}
        

        

        
while True:
        
    try:
        
        #First we grab the key character using i
        
        keyCharacter = stringText[i]
        

        
        #Then we grab the next character which will tell us how many characters they value will have
        
        # We also convert it to integer for future use
        
        valueLength = int(stringText[i+1])
        

        
        #Then we grab the value by slicing the string
        
        valueCharacters = stringText[i+2:i+2+valueLength]
        

        
        #We add this to the dictionary
        
        myDictionary[keyCharacter] = valueCharacters
        

        
        #We update i to continue where we left off
        
        i = i+2+valueLength
        

        

        
    except IndexError:
        
        break
        

        
print myDictionary


        Instead of the "try and except" you could also see how long that string is and do and if statement to break the loop when i is bigger than the length of the string.






        share|improve this answer












        This worked for me



        stringText = "A2.)43@|@C3::#"
        

        

        
i=0
        
myDictionary = {}
        

        

        
while True:
        
    try:
        
        #First we grab the key character using i
        
        keyCharacter = stringText[i]
        

        
        #Then we grab the next character which will tell us how many characters they value will have
        
        # We also convert it to integer for future use
        
        valueLength = int(stringText[i+1])
        

        
        #Then we grab the value by slicing the string
        
        valueCharacters = stringText[i+2:i+2+valueLength]
        

        
        #We add this to the dictionary
        
        myDictionary[keyCharacter] = valueCharacters
        

        
        #We update i to continue where we left off
        
        i = i+2+valueLength
        

        

        
    except IndexError:
        
        break
        

        
print myDictionary


        Instead of the "try and except" you could also see how long that string is and do and if statement to break the loop when i is bigger than the length of the string.







        share|improve this answer












        share|improve this answer



        share|improve this answer










        answered Nov 12 at 23:30









        Alvaro Bataller

        515




        515






























            draft saved

            draft discarded




















































            Thanks for contributing an answer to Stack Overflow!


            • Please be sure to answer the question. Provide details and share your research!

            But avoid …



            • Asking for help, clarification, or responding to other answers.

            • Making statements based on opinion; back them up with references or personal experience.


            To learn more, see our tips on writing great answers.





            Some of your past answers have not been well-received, and you're in danger of being blocked from answering.


            Please pay close attention to the following guidance:


            • Please be sure to answer the question. Provide details and share your research!

            But avoid …



            • Asking for help, clarification, or responding to other answers.

            • Making statements based on opinion; back them up with references or personal experience.


            To learn more, see our tips on writing great answers.




            draft saved


            draft discarded














            StackExchange.ready(
            function () {
            StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53271009%2fhow-to-read-one-character-from-a-file-as-a-key-into-a-dictionary-then-make-the%23new-answer', 'question_page');
            }
            );

            Post as a guest















            Required, but never shown





















































            Required, but never shown














            Required, but never shown












            Required, but never shown







            Required, but never shown

































            Required, but never shown














            Required, but never shown












            Required, but never shown







            Required, but never shown







            -

            Popular posts from this blog

            Guess what letter conforming each word

            Image
            6 $begingroup$ This is an entry in the Fortnightly Topic Challenge #41: Short and Sweet. 1 letter only could be mean anything . With an additional letter in front , could be used as medicine component and something you definitely learn or at least heard once. Add another letter in front , you would possibly hear that many times . Add an additional letter in front , you would found an independent country . With an additional letter, in the end , you would found something related to apple . Add another letter in the end , you would found something bad . Hint: Each letter is unique . word knowledge letters chemistry share | improve this question ...
            Read more

            Port of Spain

            Image
            For ports in the country of Spain, see List of ports in Spain. City in City of Port of Spain, Trinidad and Tobago Port of Spain City City of Port of Spain Top to bottom (left to right): Skyline of Port of Spain from Gulf of Paria; National Academy for the Performing Arts, Independence Square, Eric Williams Plaza; MovieTowne, Port of Port of Spain Motto(s):  "We Gather Strength As We Go Along" Port of Spain Coordinates: 10°40′N 61°31′W  /  10.667°N 61.517°W  / 10.667; -61.517 Coordinates: 10°40′N 61°31′W  /  10.667°N 61.517°W  / 10.667; -61.517 Country   Trinidad and Tobago Jurisdiction City of Port of Spain Settled 1560 Incorporated (town) 1853 Incorporated (city) 1914 Government  • Mayor Joel Martinez  • Governing body City Corporation Area [1]  • City 12 km 2 (5 sq mi) Elevation [2] 66 m (217 ft) Population (2011) [1]  • City 37,074  • Rank 3rd  • Density 3,090/km 2 (8,000/sq mi)...
            Read more

            Run scheduled task as local user group (not BUILTIN)

            Image
            0 I am trying to run a scheduled task with User Group (not a single user). This is working fine when I in the field "when running a task, use the following user account:" insert BUILTIN User Group (for example: Administrators or Users). But when I try it with the created Local User Group (example: TestGroup) it is not working. The Users in the TestGroup are the same as in the Administrators group. What could be the problem? Are there some restrictions to the Created User Group compared to BUILTINUsers? scheduled-tasks taskscheduler windowstaskschedule share | improve this question asked Nov 15 '18 at 15:36 Far...
            Read more