无法对txt文件中的数据进行分组

Question

I'm a beginner coder and the project I have requires me to categorize a text file. The txt file I'm opening is something like this: (this isn't fully how the txt file looks like it's just that when I copied and past it, it looked too messy. there was just another column that was just filled with the word 'map' for some reason)

 MAG UTC DATE-TIME LAT LON DEPTH Region 4.3 2014/03/12 20:16:59 25.423 -109.730 10.0 GULF OF CALIFORNIA 5.2 2014/03/12 20:09:55 36.747 144.050 24.2 JAPAN 5.0 2014/03/12 20:08:25 35.775 141.893 24.5 JAPAN 4.8 2014/03/12 19:59:01 38.101 142.840 17.6 Japan 4.6 2014/03/12 19:55:28 37.400 142.384 24.7 JAPAN 5.0 2014/03/12 19:45:19 -6.187 154.385 62.0 GUINEA 

I want the output to be something like this:

[[japan,'4.3','5.2','5.0','4.8','4.6'],[Gulf of California,4.3],[Guinea,5.0]]

my current coding: (The vlist[7:] in the first for loop gives me the region name and the j[1] in the second for loop gives me the magtitude number.)

def myOpen(filepointer):
    header = filepointer.readline()
    regions = []#gathers up all the names of the regions without repeating them
    maglist = []#matchs with naems and numbers
    filelines = []#list of lines in txt file


    for aline in filepointer:#reades each line
       vlist = aline.split()#turns lines into lists
       filelines.append(vlist)
       if not vlist[7:] in regions:#makes list of names without repeat
            regions.append(vlist[7:])
            regions.sort()

   for j in filelines:#gets each file line
        for names in regions:#each name
           if names == j[7:]:
               num = j[1]
               names.append(float(num))
               mags.append(names)
   return maglist
def main():
    myFile = open('earthquakes.txt','r')
    quakes = myOpen(myFile)
    myFile.close()
    print(quakes)

main()

gives an output of this:

[[japan,'4.3'],[Gulf of California,4.3],[Guinea,5.0]]

I'm wondering why it only gets the first magnitude number that appears for the other regions and not the rest.

Answer 1

Here you go: using itertools.groupby , lambda , map , str.split , str.lower and str.join

if your file look like this:

MAG     UTC DATE-TIME             LAT         LON      DEPTH    Region
4.3    2014/03/12 20:16:59       25.423     -109.730   10.0     GULF OF CALIFORNIA
5.2    2014/03/12 20:09:55       36.747      144.050   24.2     JAPAN
5.0    2014/03/12 20:08:25       35.775      141.893   24.5     JAPAN
4.8    2014/03/12 19:59:01       38.101      142.840   17.6     Japan
4.6    2014/03/12 19:55:28       37.400      142.384   24.7     JAPAN
5.0    2014/03/12 19:45:19       -6.187      154.385   62.0     GUINEA

here is the working code:

>>> import itertools
>>> f = open('file.txt')
>>> [[" ".join(x),list(map(lambda z:z[0],list(y)))] for x,y in itertools.groupby(sorted(list(map(str.split,map(str.lower,list(f)[1:]))),key=lambda x:" ".join(x[6:])),key=lambda x:x[6:])]
[['guinea', ['5.0']], ['gulf of california', ['4.3']], ['japan', ['5.2', '5.0', '4.8', '4.6']]]

Let me explain you:

>>> f = open('file.txt')
>>> k = list(map(str.lower,list(f)[1:]))  # convert all lines to lower case and leave 1st line
>>> k
['4.3    2014/03/12 20:16:59       25.423     -109.730   10.0     gulf of california\n', '5.2    2014/03/12 20:09:55       36.747      144.050   24.2     japan\n', '5.0    2014/03/12 20:08:25       35.775      141.893   24.5     japan\n', '4.8    2014/03/12 19:59:01       38.101      142.840   17.6     japan\n', '4.6    2014/03/12 19:55:28       37.400      142.384   24.7     japan\n', '5.0    2014/03/12 19:45:19       -6.187      154.385   62.0     guinea\n']
>>> k = list(map(str.split,k))   # it will split the lines on whitespaces
>>> k
[['4.3', '2014/03/12', '20:16:59', '25.423', '-109.730', '10.0', 'gulf', 'of', 'california'], ['5.2', '2014/03/12', '20:09:55', '36.747', '144.050', '24.2', 'japan'], ['5.0', '2014/03/12', '20:08:25', '35.775', '141.893', '24.5', 'japan'], ['4.8', '2014/03/12', '19:59:01', '38.101', '142.840', '17.6', 'japan'], ['4.6', '2014/03/12', '19:55:28', '37.400', '142.384', '24.7', 'japan'], ['5.0', '2014/03/12', '19:45:19', '-6.187', '154.385', '62.0', 'guinea']] 
>>> k = sorted(k,key = lambda x:" ".join(x[6:]))  # it will sort the k on Region
>>> k
[['5.0', '2014/03/12', '19:45:19', '-6.187', '154.385', '62.0', 'guinea'], ['4.3', '2014/03/12', '20:16:59', '25.423', '-109.730', '10.0', 'gulf', 'of', 'california'], ['5.2', '2014/03/12', '20:09:55', '36.747', '144.050', '24.2', 'japan'], ['5.0', '2014/03/12', '20:08:25', '35.775', '141.893', '24.5', 'japan'], ['4.8', '2014/03/12', '19:59:01', '38.101', '142.840', '17.6', 'japan'], ['4.6', '2014/03/12', '19:55:28', '37.400', '142.384', '24.7', 'japan']]
>>> [[" ".join(x),list(map(lambda z:z[0],list(y)))] for x,y in itertools.groupby(k,key = lambda x:x[6:])]
[['guinea', ['5.0']], ['gulf of california', ['4.3']], ['japan', ['5.2', '5.0', '4.8', '4.6']]]