Optimizing Objective-c code - iphone

Question

I have a block of code that I am trying to optimize. The method is being used a lot so any little improvement would greatly increase performance.
- (CGRect)calculateRectForItemAtIndex:(NSIndexPath*)path {
//Get the x position stored in an NSMutableArray
double x = [self.sectionXPlacementArray[path.section] doubleValue];
double y = 0;
double height = 0;
//If this is the first row it is a header so treat it different
if (path.row == 0) {
height = self.defaultHeaderHeight;
y = 0;
}
else {
height = self.defaultHeight;
//Calculate the Y placement
y = (path.row-1)*self.defaultHeight+self.defaultHeaderHeight;
}
//Build and return a CGRect
return CGRectMake(x, y, [self.headerSizes[self.headers[path.section]] doubleValue],height);
}
Here is some more information:
1) headerSizes is a NSMutableDictionary that looks like so:
{
Header1 = 135;
Header2 = 130;
Header3 = 130;
}
2) headers is a NSMutableArray that looks like this:
(
Header1,
Header2,
Header3
)
These values in the app will not be Header_. They will be dynamic NSStrings like "City" or "State". headerSizes will contain the width that should be used for each header.

Answer 1

As another person commented, this does NOT look like a method that would be slowing anything down. It's involved in laying something out, right? Or drawing something? That should not be happening very often (i.e. 60 times per second at worst). Do you actually have any evidence that this is the bottleneck? Like, have you run your code through the Profiler template in Instruments? And this showed up as the #1 top method in an inverted-call-tree view of the data?
That said, there's not much to pare down here. I did my best...
- (CGRect)calculateRectForItemAtIndex:(NSIndexPath*)path
{
//Get the x position stored in an NSMutableArray
const NSUInteger pathSection = path.section;
const NSUInteger pathRow = path.row;
const float x = [self.sectionXPlacementArray[pathSection] floatValue];
float y = 0;
float height = 0;
//If this is the first row it is a header so treat it different
if (pathRow == 0) {
height = self.defaultHeaderHeight;
y = 0;
}
else {
const float defaultHeight = self.defaultHeight;
height = defaultHeight;
//Calculate the Y placement
y = (pathRow-1)*defaultHeight+self.defaultHeaderHeight;
}
//Build and return a CGRect
return CGRectMake(x, y, [self.headerSizes[self.headers[pathSection]] floatValue], height);
}