How can I add multiple unique random values to a Pandas DataFrame efficiently?












0















I have a string of length 20, with about 30% 0's and 70% 1's. So something like this '11101001110111011110'



I would like to generate 10 more strings with the same 1, 0 distribution.



Right now I can do this by calling



''.join(map(str, np.random.choice([0, 1], size=20, p=[0.3, 0.7])))


10 times.



However, for efficiency reasons, is it possible for me to call random.choice as few times as possible, perhaps once?
Right now I'm accomplishing this by creating a dataframe and then adding a column that calls the above functions, like this.



df = pd.DataFrame([None]*10)
df['Stuff'] = ''.join(map(str, np.random.choice([0, 1], size=20, p=[0.3,
0.7])))
df


However, each of the 10 values are the same.
How do I make them unique randomized values?



If not is there some way to 'vectorize' the np.random function so my process of generating these random numbers can be more efficient?



Thanks!










share|improve this question



























    0















    I have a string of length 20, with about 30% 0's and 70% 1's. So something like this '11101001110111011110'



    I would like to generate 10 more strings with the same 1, 0 distribution.



    Right now I can do this by calling



    ''.join(map(str, np.random.choice([0, 1], size=20, p=[0.3, 0.7])))


    10 times.



    However, for efficiency reasons, is it possible for me to call random.choice as few times as possible, perhaps once?
    Right now I'm accomplishing this by creating a dataframe and then adding a column that calls the above functions, like this.



    df = pd.DataFrame([None]*10)
    df['Stuff'] = ''.join(map(str, np.random.choice([0, 1], size=20, p=[0.3,
    0.7])))
    df


    However, each of the 10 values are the same.
    How do I make them unique randomized values?



    If not is there some way to 'vectorize' the np.random function so my process of generating these random numbers can be more efficient?



    Thanks!










    share|improve this question

























      0












      0








      0








      I have a string of length 20, with about 30% 0's and 70% 1's. So something like this '11101001110111011110'



      I would like to generate 10 more strings with the same 1, 0 distribution.



      Right now I can do this by calling



      ''.join(map(str, np.random.choice([0, 1], size=20, p=[0.3, 0.7])))


      10 times.



      However, for efficiency reasons, is it possible for me to call random.choice as few times as possible, perhaps once?
      Right now I'm accomplishing this by creating a dataframe and then adding a column that calls the above functions, like this.



      df = pd.DataFrame([None]*10)
      df['Stuff'] = ''.join(map(str, np.random.choice([0, 1], size=20, p=[0.3,
      0.7])))
      df


      However, each of the 10 values are the same.
      How do I make them unique randomized values?



      If not is there some way to 'vectorize' the np.random function so my process of generating these random numbers can be more efficient?



      Thanks!










      share|improve this question














      I have a string of length 20, with about 30% 0's and 70% 1's. So something like this '11101001110111011110'



      I would like to generate 10 more strings with the same 1, 0 distribution.



      Right now I can do this by calling



      ''.join(map(str, np.random.choice([0, 1], size=20, p=[0.3, 0.7])))


      10 times.



      However, for efficiency reasons, is it possible for me to call random.choice as few times as possible, perhaps once?
      Right now I'm accomplishing this by creating a dataframe and then adding a column that calls the above functions, like this.



      df = pd.DataFrame([None]*10)
      df['Stuff'] = ''.join(map(str, np.random.choice([0, 1], size=20, p=[0.3,
      0.7])))
      df


      However, each of the 10 values are the same.
      How do I make them unique randomized values?



      If not is there some way to 'vectorize' the np.random function so my process of generating these random numbers can be more efficient?



      Thanks!







      python pandas






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      asked Nov 25 '18 at 3:43









      CalculasiansCalculasians

      42




      42
























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          The problem with your example is that you assign a single value to the whole df. You could just build a list comprehension for this.



          l1 = [str(np.random.choice([0, 1], size = 20, p = [0.3, 0.7])) for i in range(len(df.index))]
          df = df.assign(Stuff=l1)


          Other way to make this work out is by creating the values in a numpy array, like:



          array = np.fromiter((str(np.random.choice([0, 1], size = 20, p = [0.3, 0.7])) for x in range(10)), dtype=float)


          If you want, you could look for the dtypes for this, since the string type raises an error. These are the ways I could figure it out. Good luck!






          share|improve this answer

























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            1 Answer
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            1 Answer
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            active

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            active

            oldest

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            1














            The problem with your example is that you assign a single value to the whole df. You could just build a list comprehension for this.



            l1 = [str(np.random.choice([0, 1], size = 20, p = [0.3, 0.7])) for i in range(len(df.index))]
            df = df.assign(Stuff=l1)


            Other way to make this work out is by creating the values in a numpy array, like:



            array = np.fromiter((str(np.random.choice([0, 1], size = 20, p = [0.3, 0.7])) for x in range(10)), dtype=float)


            If you want, you could look for the dtypes for this, since the string type raises an error. These are the ways I could figure it out. Good luck!






            share|improve this answer






























              1














              The problem with your example is that you assign a single value to the whole df. You could just build a list comprehension for this.



              l1 = [str(np.random.choice([0, 1], size = 20, p = [0.3, 0.7])) for i in range(len(df.index))]
              df = df.assign(Stuff=l1)


              Other way to make this work out is by creating the values in a numpy array, like:



              array = np.fromiter((str(np.random.choice([0, 1], size = 20, p = [0.3, 0.7])) for x in range(10)), dtype=float)


              If you want, you could look for the dtypes for this, since the string type raises an error. These are the ways I could figure it out. Good luck!






              share|improve this answer




























                1












                1








                1







                The problem with your example is that you assign a single value to the whole df. You could just build a list comprehension for this.



                l1 = [str(np.random.choice([0, 1], size = 20, p = [0.3, 0.7])) for i in range(len(df.index))]
                df = df.assign(Stuff=l1)


                Other way to make this work out is by creating the values in a numpy array, like:



                array = np.fromiter((str(np.random.choice([0, 1], size = 20, p = [0.3, 0.7])) for x in range(10)), dtype=float)


                If you want, you could look for the dtypes for this, since the string type raises an error. These are the ways I could figure it out. Good luck!






                share|improve this answer















                The problem with your example is that you assign a single value to the whole df. You could just build a list comprehension for this.



                l1 = [str(np.random.choice([0, 1], size = 20, p = [0.3, 0.7])) for i in range(len(df.index))]
                df = df.assign(Stuff=l1)


                Other way to make this work out is by creating the values in a numpy array, like:



                array = np.fromiter((str(np.random.choice([0, 1], size = 20, p = [0.3, 0.7])) for x in range(10)), dtype=float)


                If you want, you could look for the dtypes for this, since the string type raises an error. These are the ways I could figure it out. Good luck!







                share|improve this answer














                share|improve this answer



                share|improve this answer








                edited Nov 25 '18 at 8:01









                dataLeo

                6031419




                6031419










                answered Nov 25 '18 at 5:07









                Pedro MorescoPedro Moresco

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                214






























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