I am trying read a file and split a cell in each line by a comma and then display only the first and the second cells which contain information regarding the latitude and the longitude. This is the file:
time,latitude,longitude,type
2015-03-20T10:20:35.890Z,38.8221664,-122.7649994,earthquake
2015-03-20T10:18:13.070Z,33.2073333,-116.6891667,earthquake
2015-03-20T10:15:09.000Z,62.242,-150.8769,earthquake
My program:
def getQuakeData():
filename = input("Please enter the quake file: ")
readfile = open(filename, "r")
readlines = readfile.readlines()
Type = readlines.split(",")
x = Type[1]
y = Type[2]
for points in Type:
print(x,y)
getQuakeData()
When I try to execute this program, it gives me an error
AttributeError: 'list' object has no attribute 'split'
Please help me!
I think you've actually got a wider confusion here.
The initial error is that you're trying to call split
on the whole list of lines, and you can't split
a list of strings, only a string. So, you need to split
each line, not the whole thing.
And then you're doing for points in Type
, and expecting each such points
to give you a new x
and y
. But that isn't going to happen. Types
is just two values, x
and y
, so first points
will be x
, and then points will be y
, and then you'll be done. So, again, you need to loop over each line and get the x
and y
values from each line, not loop over a single Types
from a single line.
So, everything has to go inside a loop over every line in the file, and do the split
into x
and y
once for each line. Like this:
def getQuakeData():
filename = input("Please enter the quake file: ")
readfile = open(filename, "r")
for line in readfile:
Type = line.split(",")
x = Type[1]
y = Type[2]
print(x,y)
getQuakeData()
As a side note, you really should close
the file, ideally with a with
statement, but I'll get to that at the end.
Interestingly, the problem here isn't that you're being too much of a newbie, but that you're trying to solve the problem in the same abstract way an expert would, and just don't know the details yet. This is completely doable; you just have to be explicit about mapping the functionality, rather than just doing it implicitly. Something like this:
def getQuakeData():
filename = input("Please enter the quake file: ")
readfile = open(filename, "r")
readlines = readfile.readlines()
Types = [line.split(",") for line in readlines]
xs = [Type[1] for Type in Types]
ys = [Type[2] for Type in Types]
for x, y in zip(xs, ys):
print(x,y)
getQuakeData()
Or, a better way to write that might be:
def getQuakeData():
filename = input("Please enter the quake file: ")
# Use with to make sure the file gets closed
with open(filename, "r") as readfile:
# no need for readlines; the file is already an iterable of lines
# also, using generator expressions means no extra copies
types = (line.split(",") for line in readfile)
# iterate tuples, instead of two separate iterables, so no need for zip
xys = ((type[1], type[2]) for type in types)
for x, y in xys:
print(x,y)
getQuakeData()
Finally, you may want to take a look at NumPy and Pandas, libraries which do give you a way to implicitly map functionality over a whole array or frame of data almost the same way you were trying to.