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Tuplelist access?
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The comments are running willy-nilly, but at least in the pre-view mode it helps to click "Toggle Plain Text".
Now, option 2 returns Nope regardless of wether the word you enter was entered into the list under option 1 before or not.
So what I'm trying to get to grips with is how to make python realise that the word entered is in the list. Or, to put it another way, to use the variable "word" under both 1 and 2 as a dictionary keyword.
Sheesh, I really have a long way to go...
if wish == 1: #Menu option
word = input("Enter word: ")
description = input("Enter description: ")
print
print
tuplelist.append((word,description)) #tuplelist is originally
defined as simply []
main_dictuples(tuplelist) #Returns the function
for the main menu;
ideally updating tuplelist
with a new tuple
at the last position...
if wish == 2: #Menu option
word = input("Enter word to look up: ") #Shortened version,
but you get the idea
if word in tuplelist:
print "Yep"
else:
print "Nope"Now, option 2 returns Nope regardless of wether the word you enter was entered into the list under option 1 before or not.
So what I'm trying to get to grips with is how to make python realise that the word entered is in the list. Or, to put it another way, to use the variable "word" under both 1 and 2 as a dictionary keyword.
Sheesh, I really have a long way to go...
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Join Date: May 2008
Posts: 942
Reputation: 
Solved Threads: 146
previously paulthom12345
when you go.
That is a problem. The reason is your comparing something that looks like this:
To something that looks like this
Now those dont look quite the same right?
So what you need to do is say,
That might not be the most efficient way but it will work better.
python Syntax (Toggle Plain Text)
python Syntax (Toggle Plain Text)
python Syntax (Toggle Plain Text)
So what you need to do is say,
python Syntax (Toggle Plain Text)
Last edited by Paul Thompson; Oct 19th, 2008 at 5:12 pm.
Make it idiot proof and someone will make a better idiot.
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Thanks for the quick reply, now at least I understand that much more. Just one more of those staring-at-semantics-error-not-getting-what-the-syntax-wants-problems:
As far as I understand, the operation you provided means that the program identifies the tuple we're after and thus, asking it to print f[1] should give the other half of the tuple, in this case the description. But say for example that I first enter ("Hello","Greeting") under option 1 and then also add in ("No","Refusal") and then ask it to look up the word "Hello":
It answers "Refusal".
I thought this setup would create a new tuple for each new entry? Or is it just me misunderstanding what the program does when looking up?
Sorry for the daft questions...
As far as I understand, the operation you provided means that the program identifies the tuple we're after and thus, asking it to print f[1] should give the other half of the tuple, in this case the description. But say for example that I first enter ("Hello","Greeting") under option 1 and then also add in ("No","Refusal") and then ask it to look up the word "Hello":
It answers "Refusal".
I thought this setup would create a new tuple for each new entry? Or is it just me misunderstanding what the program does when looking up?
Sorry for the daft questions...
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Join Date: Jul 2008
Posts: 963
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Posting Shark
You could use this, if you want to access the tuples
However, a more efficient way to do this would be to use dictionaries.
python Syntax (Toggle Plain Text)
Last edited by Gribouillis; Oct 19th, 2008 at 6:36 pm.
It would, this is just a matter of me wanting to understand this completely; the way I see it, you don't get good at things by ignoring the parts you don't grasp immediately.
Still, though, there seems to be things I mess up:
I've experimented quite a bit and I know that the list itself looks like it should. For example I did like this:
... and it writes tuplelist exactly the way I want it. But it won't let me indetify the index of a particular tuple.
If I write like this:
... it evidently recognizes the word I entered (if it wasn't in the list it'd return "Nope", which it doesn't), and prints tuplelist looking good with the right word and description paired together. But it interprets item[1] to be the second part of the
last tuple.
Say for example I've made the three entries
"Hello" and "Greeting"
"No" and "Refusal"
"What" and "Wondering"
the snippet above will return
[('Hello', 'Greeting'), ('No', 'Refusal'), ('What', 'Wondering')]
Wondering
even if I told it to look for the word "Hello". Even if, and this is making me really lost in the fog, I do like this (the same entries in the list as before):
it simply returns a variation on the above:
[('Hello', 'Greeting'), ('No', 'Refusal'), ('What', 'Wondering')]
('Va', 'Wondering')
So, well, um... help?
Still, though, there seems to be things I mess up:
I've experimented quite a bit and I know that the list itself looks like it should. For example I did like this:
word = input("Enter word to look up: ")
selection = [item for item in tuplelist if item[0] == word]
if selection:
print
print
print tuplelist
else:
print "Nope"... and it writes tuplelist exactly the way I want it. But it won't let me indetify the index of a particular tuple.
If I write like this:
word = input("Enter word to look up: ")
selection = [item for item in tuplelist if item[0] == word]
if selection:
print
print
print tuplelist
print
print
print item[1]
else:
print "Nope"... it evidently recognizes the word I entered (if it wasn't in the list it'd return "Nope", which it doesn't), and prints tuplelist looking good with the right word and description paired together. But it interprets item[1] to be the second part of the
last tuple.
Say for example I've made the three entries
"Hello" and "Greeting"
"No" and "Refusal"
"What" and "Wondering"
the snippet above will return
[('Hello', 'Greeting'), ('No', 'Refusal'), ('What', 'Wondering')]
Wondering
even if I told it to look for the word "Hello". Even if, and this is making me really lost in the fog, I do like this (the same entries in the list as before):
word = input("Enter word to look up: ")
selection = [item for item in tuplelist if item[0] == word]
if selection:
a = tuplelist.index(item)
print
print
print tuplelist[a]
else:
print "Nope"it simply returns a variation on the above:
[('Hello', 'Greeting'), ('No', 'Refusal'), ('What', 'Wondering')]
('Va', 'Wondering')
So, well, um... help?
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Posts: 963
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Solved Threads: 221
Posting Shark
Don't use item after the
selection=... . in this expression, item varies from the first element to the last element of the list. You can use selection , which is a list of all the tuples in tuplelist which first element is word. You could obtain a list of indexes instead, like this python Syntax (Toggle Plain Text)
Well, I got something working, looks like this:
Thanks for the input guys, it was very helpful, not to mention useful!
word = input("Enter word to look up: ")
selection = [item for item in tuplelist if item[0] == word]
if selection:
a = selection[0]
print
print
print a[1]
print
print
else:
print "Nope"Thanks for the input guys, it was very helpful, not to mention useful!
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