storing an array - objective-c

Question

I am trying to store the outcome of a string from the array hypothesis into myArray
am I doing anything wrong?
myArray = [NSString stringWithFormat:#"%#", hypothesis];
Update
NSMutableArray *myArray
NSMutableArray *urArray
// this is where my words are converted into strings. e.g. if I said "HELLO"
- (void) pocketsphinxDidReceiveHypothesis:(NSString *)hypothesis{
if (x==1){
// I am trying to store "HELLO" into myArray for comparison later.
myArray = [NSString stringWithFormat:#"%#", hypothesis];
// this would print "HELLO"
self.textview.text = [NSString stringWithFormat:#"You said %#",hypothesis];
}
else {
urArray = [NSString stringWithFormat:#"%#", hypothesis];
}
}
this is basically it. after that I will compare myArray == urArray in an ifelse statement.

Answer 1

Try...
myArray = [NSArray arrayWithObject:[NSString stringWithFormat:#"%#", hypothesis]];

Answer 2

Yes, you are doing several things wrong.
you have a method -pocketsphinxDidReceiveHypothesis which you have defined as taking a single argument of type NSString*, the argument is called hypothesis.
In your question you say
I am trying to store the outcome of a
string from the array hypothesis
Which suggests that you know hypothesis is an array, but we can't verify this as you don't show that piece of code.
hypothesis must be a String or an Array. It cannot be both, you cannot be unsure.
If hypothesis is a String, ie. if you do something like:
NSString *input = #"Hello World";
[foo pocketsphinxDidReceiveHypothesis: input];
Then these two lines make no sense:-
NSMutableArray *myArray = [NSString stringWithFormat:#"%#", hypothesis];
NSMutableArray *urArray = [NSString stringWithFormat:#"%#", hypothesis];
Because, well look..
NSString *hypothesis = #"Hello World";
newString = [NSString stringWithFormat:#"%#", hypothesis];
This code does nothing, hypothesis and newString are identical, as you haven't even provided any arguments for the format. [NSString stringWithFormat:#"%#", hypothesis] is no different to just using hypothesis. So what you actually have is
NSString *hypothesis;
NSMutableArray *myArray = hypothesis;
NSMutableArray *urArray = hypothesis;
This is broken, you cant assign a String to an Array (well, i'm fairly certain you don't mean to anyhow). To use an Array you must use of of the several Array creation methods to give you, well, an Array. A String isn't an Array and can't pretend to be one.
Now, apologies if hypothesis isn't a String but is infact an Array (it would have helped if you had shown that piece of code). If it is an Array, ie. you do something like this..
NSArray *input = [NSArray arrayWithObject:#"Hello World"];
[foo pocketsphinxDidReceiveHypothesis: input];
Then your method definition is broken because you have defined it as taking a String argument
- (void)pocketsphinxDidReceiveHypothesis:(NSString *)hypothesis
When you need it to take an Array argument
- (void)pocketsphinxDidReceiveHypothesis:(NSArray *)hypothesis
Then the following two lines make no sense:-
NSMutableArray *myArray = [NSString stringWithFormat:#"%#", hypothesis];
NSMutableArray *urArray = [NSString stringWithFormat:#"%#", hypothesis];
[NSString stringWithFormat:#"%#", hypothesis] is exactly the same as [hypothesis description], which returns a String, so what you are effectively doing is:
NSArray *hypothesis;
NSString *hypothesisDescription = [hypothesis description];
NSMutableArray *myArray = hypothesisDescription;
NSMutableArray *urArray = hypothesisDescription;
So again, assigning a String to an Array variable - almost certainly not going to do what you want or need.
If hypothesis is a String and you meant to add it to an array, you must first make sure the array is initialized (ie it has to be a valid array). Something like NSMutableArray *myArray = [[NSMutableArray alloc] init] will do the trick. Then you can use one of NSMutableArray's methods to store your String, eg. [myArray addObject:hypothesis].
If hypothesis is an Array would you like to store the it in myArray as is or would you first like to transform it into a String?
Then you go on to say:-
I will compare myArray == urArray in
an ifelse statement
Given the confusion surrounding the preceding code it is not clear why you want to do this or what you hope to achieve. You have nowhere included a description of what this code is supposed to do. It is not clear whether you are aware that two Arrays that contain identical objects are not == (as the are two different arrays and have their own identity), but two pointers to the same Array are ==, eg:
NSArray *aSimpleArray = [NSArray arrayWithObjects:#"one", #"two", #"three", nil];
NSArray *foo = aSimpleArray;
BOOL result = (aSimpleArray==foo); // These are equal, result is true
NSArray *anotherSimpleArray = [NSArray arrayWithObjects:#"one", #"two", #"three", nil];
BOOL result = (aSimpleArray==anotherSimpleArray); // These are not equal, result is false
So unless you want to test if you have two pointers to the same Array (and not just two arrays with the same objects) == probably doesn't do what you want. Note there are methods to help compare Arrays, such as -isEqualToArray, so that:
NSArray *aSimpleArray1 = [NSArray arrayWithObjects:#"one", #"two", #"three", nil];
NSArray *aSimpleArray2 = [NSArray arrayWithObjects:#"one", #"two", #"three", nil];
BOOL areEqual1 = aSimpleArray1==aSimpleArray2; // FALSE
BOO areEqual2 = [aSimpleArray1 isEqualToArray:aSimpleArray2]; // TRUE
In general you have to be familiar with the interfaces of all the objects you are going to use
http://developer.apple.com/library/ios/#documentation/cocoa/reference/foundation/Classes/NSArray_Class/NSArray.html
The Apple documentation is excellent but i recommend a good book. There are many posts about book recommendations on SO so i leave that to you. Otherwise Apple provides hundreds of simple sample projects that you should study.

Answer 3

Are you trying to add hypothesis to one of your arrays (i.e. your arrays are arrays of multiple hypotheses)? If so then you can use addObject:
[myArray addObject:hypothesis];
If the hypothesis string is actually supposed to represent the entire array then you'll need to explain how the elements are encoded into this string before we can help you.

Answer 4

I am trying to store the same text
that hypothesis is holding into
myArray.
In that case:
NSArray *myArray = nil;
…
myArray = [NSArray arrayWithObject:hypthesis];
But mainly I would suggest that you go through some good Objective-C tutorial, since you seem to be confusing many basic ideas and it’s hard to get somewhere without knowing the basics.