Python Map List of Strings to Integer List

Question

Let\'s say I have a list

l = [\'michael\',\'michael\',\'alice\',\'carter\']

I want to map it to the following:

k = [1,1,2,3         


        

Answer 1

In order to answer the edited question, i.e., to map the list of strings to unique integers, one has to first find the unique strings and then do 1-1 mapping of the strings to integers in the original list of strings. For example,

s = ['michael','michael','alice','carter']

then unique strings are {'michael','alice','carter'}. Now, convert these strings to integers by 1-1 mapping like {'michael','alice','carter'} =[1,2,3] using dictionary {'michael':1,'alice':2,'carter':3}. In the third step, loop through the original list of strings; search the string in the dictionary for the corresponding integer and replace the string by that integer.

s=['michael','michael','alice','carter']

mydict={}
i = 0
for item in s:
    if(i>0 and item in mydict):
        continue
    else:    
       i = i+1
       mydict[item] = i

k=[]
for item in s:
    k.append(mydict[item])

Output:

k=[1, 1, 2, 3]