Moving row 2 to row 5 results in:
0 1 3 4 5 2 6
or the row being placed *after* the target row.

While moving row 5 to row 2 results in:
0 1 5 2 3 4 6
or the row being placed *before* the target row.

What you’re actually doing here is to get a float value from an array “y”, check if this is larger than 10 and the result (a boolean “YES” or “NO”) is then used to create a NSNumber again… where the BOOL is interpreted as float.
So the condition is actually only checking if creating a float from a BOOL did create an object.

My advice, especially if you are new to programming:

• Use the debugger to check the content of variables.
• Split up lines into more basic calculations and assign the intermediate results to separate variables. This way you can check these intermediate results and you’ll be able to find the location where it starts to go wrong much more easier. Such a line as in your code where everything is squeezed into one line makes it only hard to find errors.
• Watch out for compiler warnings. If the compiler warns you about something, look closer, it almost always has a reason that there’s a warning. And usually there warnings already give you an idea about what is wrong.

When i call this if condition, The condition inside the if does not get executed. Code used to call an element

if([NSNumber numberWithFloat:(([[[shared instance].y objectAtIndex:0] floatValue]))>10])
{
[MONObject sharedInstance1[.counterPlus++; //counter used to update the value
}

Counter value gets updated irrespective of the condition inside if? Is this the way to get a element from the array and compare?

Note: i have created a single tone array! Please help me!
Seems like the there is a bug inside the condition! Any thought?

Also I guess your variable “counterplus” should be an “int” and not a pointer to an int (“int*”).

@interface MONObject : NSObject {
   int *counterplus;
}
@property(nonatomic) int *counterplus;
+(MONbject*) sharedinstance;
@end

In the .m file

static MON object * sharedinstance;
@implementation MONbject;
@synthesize counterplus;

+(MONbject*)sharedinstance
{
   if(!sharedinstance){
      sharedinstance=[[MONObject alloc]init];
   }
   return sharedinstance
}
-(MONObject*) int
{
   self=[super init];
   if(0!=self){
      counterplus=0;
   }
   return self;
}
@end

I call the above as…

if(condition){
   [MONObject sharedinstance].counterplus++;
}

when i try to print the value of it using NSlog, program stops and give this error
“single stepping until exit from function objc_msgSend, which has no line number informatiopn. warning remote failure reply: E37

I have no clue at all. I tried to used a global variable by defining it as extern and tried to
increment. But it give the same error.
Is there any way to achieve this? Can you please point me the error in it~
Pleaseeeeeeeeeeeeee…………

The first part, adding new numbers to the top and only keeping 4 elements in the array, is really easy:

float myNewFloat = 1.0f;
NSNumber *myNewNumber = [NSNumber numberWithFloat: myNewFloat];
[myNSMutableArray insertObject: myNewNumber atIndex: 0];
if (myNSMutableArray.count > 4) {
    [myNSMutableArray removeLastObject];
}

As for your calculations, you’ll want to enumerate your array, which means to step through it one element at a time. Here’s an example which computes the total sum of all elements, assuming you have an array of NSNumber objects:

float myTotal = 0.0f;
for (NSNumber *num in myNSMutableArray)
{
    float fnum = [NSNumber floatValue];
    myTotal += fnum;
}
NSLog(@"Total of all elements in array is: %0.3f", myTotal);

If you get stuck again, I’d recommend reading the documentation on Cocoa and NSObject in general. The basic stuff is really well written, so don’t be scared of it. Just takes time!

You don’t want to try multiplying a value type by an object type. That won’t work, ever.
It’s probably easiest if you do all of your calculations on your float values, and just use NSNumber to store and retrieve them from your arrays.

Good luck, happy learning!

float myFloat = 123.4;
NSNumber *myNumberObject = [NSNumber numberWithFloat: myFloat];

Then you can add it to an NSArray, store it in NSUserDefaults, whatever…

To get it back out again as a float value, use this;

float myRetrievedFloat = [myNumberObject floatValue];

NSMutableArray *x;
x=[NSMutableArray arrayWithObjects:@"3",@"3",nil);
float output;

i want to multiply the 1st element by number 3.34 and store in the variable output
I code...

output=([x objectAtIndex:0])*3.34;

But it gives an error!
Please help me!

But when i code,
[array insertObject:variable_name atIndex:0];
it gives a error message!
How can i add an element to this array from a variable.
Thank you!

A. insertObject:object AtIndex:index addsobject to the end of
the array if index is equal to the length of ther array.

B. Part of your code adds :object to the end of the array if index is greater
than or equal to the length of ther array

C. A impiles that all of B is redundant.

A purist will argue that moveObjectFromIndex:toIndex should handle an index parameter value the same way that insertObject:AtIndex does. You have a different philosophy, and given that you do, C is incorrect.

How great would it be if it were this easy to resolve philosophical differences? No war. More love.