Python - creating a dictionary of csv file thath collects all values with the same key without using-CodePudding

hello I took a course in python for biologists and and had hw about using csv files, and I got stuck in the final question about creating a dictionary out of csv files with keys as tuples of (c, b), and the values are lists of tuples of all (first, finish, fix/ext) values, that are of same c,b values. the csv looks like this:

N,c,g,b,first,finish,fix/ext
1000,1.0,0.02,3.0,602,1661,0
1000,0.8,0.02,3.0,42,911,0
1000,1.0,0.02,3.0,945,2164,0
1000,1.0,0.02,3.0,141,954,0

the result need to look like this:

: {(1, 3) : [(602, 1661, 0), (945, 2164, 1), (687, 716, 1)], (1, 1.5) : [(35, 287, 0), (803, 1402, 0), …], …}

for now i managed to do this:

def read_results(full_file_path):
    csv_dict = {}
    with open(full_file_path,'r') as t:
        table = t.readlines()[1:]
        for line in table:
            line = line.replace('\n', '')
            line = line.split(',')
            csv_dict[line[0]] = line[1:]
            print(csv_dict)

which gives me this:

{'1000': ['1.0', '0.02', '3.0', '602', '1661', '0']}

but cant seem to understand how to do it with the keys that i need and how put into tuples the lists of all corresponding values

oh and I cant use import csv or other imports

CodePudding user response：

You are almost done, the only thing left is to set, what is going to be your keys and what are your values. Here I wrote a code that finalises it:

def read_results(full_file_path):
    csv_dict = {}
    with open(full_file_path,'r') as t:
        table = t.readlines()[1:]
        for line in table:
            line = line.replace('\n', '')
            line = line.split(',')
            line = list(map(float, line)) # optional, if you want to have numbers as floats and not strings
            '''
            line[1] - c
            line[3] - b
            KEY: (c,b) - tuple of c and b 
            TUPLE OF CORRESPONDING VALUES: (line[4], line[5], line[6]) - tuple of first, finish, fix/ext 
            '''
            key = (line[1],line[3])
            if key in csv_dict:
                # append a new value if key is already in the dict
                csv_dict[key].append((line[4], line[5], line[6]))
            else:
                # create a new value by the key if it is not in the dict
               csv_dict[key] = [(line[4], line[5], line[6])] 
    return csv_dict
        
dict = read_results("file.csv")
print(dict)
# try to get the values of dict by some value:
key = (1.0, 3.0) #key = ("0.8", "3.0") if strings were not converted to floats
print(dict[key])

I hope I made it understandable with the corresponding comments. If you have more questions - write them down and I will try to answer them.