python - How to check strings in list -

i have string:

a = "sky high" 

and file in csv style have opened , converted list:

mylist = [["sky high",'77'],["sky high , high",'88']] 

i want check if string exist in first position in every list. but, if this:

for row in mylist:     if in row[0]:        print row[1] 

it give me result 77 88 instead of 77. don't know why can't use if a == row[0] produce no result. have idea do?

edit:

so code looks this:

data = open("text.qrel",'rb') new = [] row in data:     d = row[:-1].split(',')      if == d[0]:        new.append(d[1]) 

and doesn't work!

try running through interactive visualizer, this one. when can't reason, @ least try experimenting in normal interactive interpreter, or printing out intermediate results in program.

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when a "sky high", , row ["sky high , high",'88'], means row[0] "sky high , high", a in row[0] true.

that's why (if fix use [1] instead of [2]) print both 77 , 88.

try @ interactive interpreter (or visualizer):

>>> = "sky high" >>> mylist = [["sky high",'77'],["sky high , high",'88']] >>> row = mylist[1] >>> row[0] "sky high , high" >>> in row[0] true 

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meanwhile, "i don't know why can't use if == row[0] produce no result."

but if use a == row[0] won't produce no result; produce 77.

try @ interactive interpreter (or in online visualizer):

>>> = "sky high" >>> mylist = [["sky high",'77'],["sky high , high",'88']] >>> row in mylist: ...     if == row[0]: ...         print row[1] 77 

so, must have bug in other part of code. show version claim isn't working, , can find bug.

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most likely, problem real code row (or, actually, d) not ["sky high", '77'], characters in it:

data = open("text.qrel",'rb') new = [] row in data:     d = row[:-1].split(',') 

let's text.qrel looked this:

sky high , 77 

this make d[0] "sky high " (with space), not "sky high".

or:

"sky high",'77' 

then d[0] '"sky high"' (with quotes), not "sky high".

you show extract of csv file, or have code print out each row , show prints; otherwise, we're guessing.

you can try fix things manually. example, handle both of above cases, instead of this:

d = row[:-1].split(',') 

… you'd do:

def remove_quotes(x):     if x[0] == '"' , x[-1] == '"': return x[1:-1]     elif x[0] == "'" , x[-1] == "'": return x[1:-1]     else: return x row in data:     d = [remove_quotes(col.strip()) col in row[:-1].split(',')] 

if don't understand list comprehensions, line:

d = [remove_quotes(col.strip()) col in row[:-1].split(',')] 

… shortcut for:

d = [] col in row[:-1].split(','):     d.append(remove_quotes(col.strip()) 

you have [:-1] remove trailing \n , split(',') split 2 columns. instead of using columns as-is, on each one, call strip() remove whitespace @ edges (which turns out not matter in specific case, common problem in csvs), , call remove_quotes on result remove matched pairs of quotes, , use that column value.

as can see, that's tedious , complicated.

and there still plenty of common cases won't handle.

this why want use the csv module instead of trying parse csv files yourself:

for d in csv.reader(data): 

now, d[0] "sky high".

if csv files aren't quite "standard"-enough csv handle out-of-the-box, can give dialect object, or format parameters, reader, , it's still easier trying build scratch yourself.