how to create NSMutableArray dynamically based on certain condition in iphone

I have a array of dates, so based on certain condition of date I need to create a NSmutablearray and add some values to that particular array. so number of sections in my tableview depends on this mutablearray count(which is internally depends on condition of date).

for example:

if(date1)
1.create array1
2.add x,y,z values to the array1.

if(date2)
1.create array2
2.add xx,yy,zz values to the array2.

....

thanks..

NSMutableArray *a = [NSMutableArray array];
if (b) {
  [a addObject: ... some object based on "b" being true ...];
  ... etc ...
} else if (c) {
  [a addObject: ... some object based on "c" being true ...];
  ... etc ...
} else {
  [a addObject: ... some object based on neither "c" nor "b" being true ...];
  ... etc ...
}

[Responding to LordT's comment]

"Don't" is a strong word considering that

NSMutableArray *aMutableArray = [NSMutableArray array]; // compiles but invokes +array in NSMutableArray's parent class since +array is not declared in NSMutableArray. What you get if you inspect the object returned by the message expression is an NSArray.

If you really want to use +array but not NSMutableArray class method +arrayWithCapacity: , perhaps

NSMutableArray *aMutableArray = [[NSMutableArray array] mutableCopy];

will suffice? Just don't forget to memory manage. 8)