Find all unique in a column, do calculation from another column, and create a new csv file as output.  code:

Input:

Output:

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Read values in a csv file for calculation and then calculate a mean: code:
        
Output:
         

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Print line by line from a CSV file in dict format (these printed keys and values cannot be directly used for math calculation): code:
        
Output:
         

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Find the maximum in a column in a csv file: code:
        
Input:
         
Output:
         

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Simple calculation in csv: code:
        
Input:
         
Output:
         

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Write to a specific cell (loc[]) in a csv file: code:
                  
Output:         
         

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Collect the corresponding string elements in column "X" as individual strings when the corresponding elements in column "Y" are "Z". code: 

Output:

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Subset of dataframe under conditons. code: 

Output:

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