Re: [Tutor] Tutor Digest, Vol 50, Issue 9
Kepala Pening wrote:
> import re
>
> items = []
> for line in open('data.txt'):
> items.append(re.sub('\n', '', line).split(' '))
Hmm. So much to say about so little code!
- the re.sub() is not needed - the split() will remove the trailing newline:
In [53]: 'a b\n'.split()
Out[53]: ['a', 'b']
- you don't need re to replace a fixed character, you can use str.replace():
In [55]: 'a b\n'.replace('\n', '')
Out[55]: 'a b'
- If you just want to strip the trailing newline you can use strip() or
rstrip(), with or without args, depending on how strict you want to be:
In [56]: 'a b\n'.strip()
Out[56]: 'a b'
- It's not clear that the OP wants a list of lines, but if so, a list
comprehension is much more succinct:
items = [ line.split() for line in open('data.txt') ]
would do the job just fine.
Kent
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Re: [Tutor] Tutor Digest, Vol 50, Issue 9
import re
items = []
for line in open('data.txt'):
items.append(re.sub('\n', '', line).split(' '))
- Original Message -
From: "Gloom Demon" <[EMAIL PROTECTED]>
To: tutor@python.org
Date: Wed, 9 Apr 2008 15:29:35 +0300
Subject: Re: [Tutor] Tutor Digest, Vol 50, Issue 9
Hello :-)
Can someone please explain to me ho can I find out how many elements are
there in one record of a list?
The problem is as follows:
I have a txt file from which I read data into Python.
The file looks something like this:
01 bla bla bla 23,15 2345,67
02 alb alb 2,4 890,1
03 bal bla alb lab 567,12345 87,45
I need to be able to discriminate the string parts from the numeric ones.
Since the number of words in the file can vary, I have to be able to find out
when they are finished
and when the floats come in
mystring[0]-> always integer
mystring[1]-> string (word)
mystring[1-X]-> last string (word)
mystring[X+1]-> always float
mystring[X+2]-> always float
it would have been nice if I could find out the total number of the fields in
one list record so that I could then adress them via a variable.
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Re: [Tutor] Tutor Digest, Vol 50, Issue 9
On Wed, Apr 9, 2008 at 12:59 PM, rui <[EMAIL PROTECTED]> wrote:
> Hi Gloom,
>
>
>
> You should give a look at the method "split" (of the string objects) and
> int.
>
> The first is used do break a string into smaller pieces and the other to
> convert a string to an int object, raising an exception when it is not
> possible.
>
>
> On Wed, Apr 9, 2008 at 9:29 AM, Gloom Demon <[EMAIL PROTECTED]> wrote:
>
> > Hello :-)
> >
> > Can someone please explain to me ho can I find out how many elements are
> > there in one record of a list?
> >
> > The problem is as follows:
> >
> > I have a txt file from which I read data into Python.
> >
> > The file looks something like this:
> >
> > 01 bla bla bla 23,15 2345,67
> > 02 alb alb 2,4 890,1
> > 03 bal bla alb lab 567,12345 87,45
> >
> >
> > I need to be able to discriminate the string
> > parts from the numeric ones.
> >
> > Since the number of words in the file can vary, I have to be able to find
> > out when they are finished
> > and when the floats come in
> >
> > mystring[0]-> always integer
> > mystring[1]-> string (word)
> > mystring[1-X]-> last string (word)
> > mystring[X+1]-> always float
> > mystring[X+2]-> always float
> >
> > it would have been nice if I could find out the total number of the
> > fields in one list record so that I could then adress them via a variable.
> >
> > ___
> > Tutor maillist - Tutor@python.org
> > http://mail.python.org/mailman/listinfo/tutor
> >
> >
>
>
> --
> Ruivaldo Neto
>
> ___
> Tutor maillist - Tutor@python.org
> http://mail.python.org/mailman/listinfo/tutor
>
>
my guess would be something like this :
a=open('/home/some_file.txt')
for line in a:
tmp_list_1=line.split()
num_floats=0
num_strings=0
for i in tmp_list_1:
if type(i) == int:
num_floats=num_floats+1
else:
num_strings=num_strings+1
if you explain more you case maybe i can get more ideas - hope this helps
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Re: [Tutor] Tutor Digest, Vol 50, Issue 9
Gloom Demon wrote: > Hello :-) > > Can someone please explain to me ho can I find out how many elements are > there in one record of a list? The len() function gives the length of a list. > I have a txt file from which I read data into Python. > > The file looks something like this: > > 01 bla bla bla 23,15 2345,67 > 02 alb alb 2,4 890,1 > 03 bal bla alb lab 567,12345 87,45 > > > I need to be able to discriminate the string parts from the numeric ones. > Since the number of words in the file can vary, I have to be able to find out > when they are finished > and when the floats come in You can also use slice indexing with negative numbers to index from the end: In [50]: data = '''01 bla bla bla 23,15 2345,67 : 02 alb alb 2,4 890,1 : 03 bal bla alb lab 567,12345 87,45 : '''.splitlines() In [51]: for line in data: : line = line.split() # Break the line at whitespace : print len(line) # Number of elements in the line : print line[1:-2] : print line[-2:] : print : : 6 ['bla', 'bla', 'bla'] ['23,15', '2345,67'] 5 ['alb', 'alb'] ['2,4', '890,1'] 7 ['bal', 'bla', 'alb', 'lab'] ['567,12345', '87,45'] Negative indices index from the end of the list, so line[1:-2] gives you the elements from line[1] up to but not including line[-2] which is the next-to-last element. Kent ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Tutor Digest, Vol 50, Issue 9
Hi Gloom, You should give a look at the method "split" (of the string objects) and int. The first is used do break a string into smaller pieces and the other to convert a string to an int object, raising an exception when it is not possible. On Wed, Apr 9, 2008 at 9:29 AM, Gloom Demon <[EMAIL PROTECTED]> wrote: > Hello :-) > > Can someone please explain to me ho can I find out how many elements are > there in one record of a list? > > The problem is as follows: > > I have a txt file from which I read data into Python. > > The file looks something like this: > > 01 bla bla bla 23,15 2345,67 > 02 alb alb 2,4 890,1 > 03 bal bla alb lab 567,12345 87,45 > > > I need to be able to discriminate the string parts from the numeric ones. > > Since the number of words in the file can vary, I have to be able to find out > when they are finished > and when the floats come in > > mystring[0]-> always integer > mystring[1]-> string (word) > mystring[1-X]-> last string (word) > mystring[X+1]-> always float > mystring[X+2]-> always float > > it would have been nice if I could find out the total number of the fields > in one list record so that I could then adress them via a variable. > > ___ > Tutor maillist - Tutor@python.org > http://mail.python.org/mailman/listinfo/tutor > > -- Ruivaldo Neto ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Tutor Digest, Vol 50, Issue 9
Hello :-) Can someone please explain to me ho can I find out how many elements are there in one record of a list? The problem is as follows: I have a txt file from which I read data into Python. The file looks something like this: 01 bla bla bla 23,15 2345,67 02 alb alb 2,4 890,1 03 bal bla alb lab 567,12345 87,45 I need to be able to discriminate the string parts from the numeric ones. Since the number of words in the file can vary, I have to be able to find out when they are finished and when the floats come in mystring[0]-> always integer mystring[1]-> string (word) mystring[1-X]-> last string (word) mystring[X+1]-> always float mystring[X+2]-> always float it would have been nice if I could find out the total number of the fields in one list record so that I could then adress them via a variable. ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
