with regression

gistfile1.txt

//
//  GOCustomView.m
//  CustomViewExample
//
//  Created by Cassidy Pangell on 8/26/11.
//  Copyright (c) 2011 __MyCompanyName__. All rights reserved.
//

#import "CPCustomView.h"
#include "math.h"
#define LENGTH 248
#define HEIGHT 250

@implementation CPCustomView
@synthesize bgColor = _bgColor;
@synthesize MVO_U_Points = _MVO_U_Points;
@synthesize MVO_D_Points = _MVO_D_Points;
@synthesize TCP_U_Points = _TCP_U_Points;
@synthesize TCP_D_Points = _TCP_D_Points;

- (void)setBgColor:(UIColor *)bgColor{
    [_bgColor release];
    _bgColor = [bgColor retain];
    [self setNeedsDisplay];
}


- (void)awakeFromNib{
    //self.bgColor = [UIColor orangeColor];
}

- (void)drawRect:(CGRect)rect
{

    [self.bgColor setFill];
    
    [self graphPoints:_MVO_D_Points];
//[self graphPoints:_MVO_U_Points];
  //  [self graphPoints:_TCP_D_Points];
    //[self graphPoints:_TCP_U_Points];

}

-(void)regression{
    
}


-(void) graphPoints:(NSMutableArray *)nsArray{

    CGContextRef context = UIGraphicsGetCurrentContext();
    CGContextSetLineWidth(context, 2.0);
    NSUInteger count = [nsArray count];
    //NSLog(@"COUNT %i",count);
    
    CGFloat prevValX;
    CGFloat prevValY;
    CGFloat currValX;
    CGFloat currValY;
    CGFloat firstValX;
    CGFloat deltaX = LENGTH / (count - 1);
    CGFloat changeDeltaX;
    NSValue runningAvg;

    CGFloat sumXYN = 0.0;
    CGFloat sumX = 0.0;
    CGFloat sumY = 0.0;
    CGFloat sumXsqN = 0.0;
    CGFloat sumXsq = 0.0;
    CGFloat slope; //b
    CGFloat intercept; //a
    CGFloat regPointOne; // a + bx => x being the point
    CGFloat regPointTwo;
    
    //allocate data points for graph
    for(int i=1; i<count; i++){  

        changeDeltaX = deltaX;
       // NSLog(@"DELTA %f", deltaX);
        NSValue *currentPointValue = [nsArray objectAtIndex:i];
        CGPoint currentPoint = [currentPointValue CGPointValue];
        NSValue *previousPointValue = [nsArray objectAtIndex:i-1];
        CGPoint previousPoint = [previousPointValue CGPointValue];
        NSValue *firstPointValue = [nsArray objectAtIndex:0];
        CGPoint firstPoint = [firstPointValue CGPointValue];
        
        while (i<15) {
            runningAvg += currentPoint.y / count;
            if(i == 14) {
                [nsArray replaceObjectAtIndex:0 withObject:runningAvg];
            }
        }
        
        
        
        if((deltaX - changeDeltaX) != 0)
        {
            NSLog(@"change");
            
           // [nsArray replaceObjectAtIndex:i withObject:x];
        }
        
        
       
        //NSLog(@"RT %f", runningAvg);
        currValX = (currentPoint.x + (deltaX * (i)));
        currValY = 250 - (currentPoint.y);
        
        NSLog(@"currValY %f", currValY);
        
        prevValX = (previousPoint.x + ((deltaX) * (i-1)));
        prevValY = 250 - (previousPoint.y);
        
        firstValX = firstPoint.y;
        //NSLog(@"FIRST %f", firstValX);
        
        //Calculate regression line for points
        sumX += currValX;
        sumY += currValY;
        sumXYN += (currValX * currValY) * count;
        sumXsqN += (currValX * currValX) * count;
        sumXsq += sumX * sumX;
        
        slope = (sumXYN - (sumX)*(sumY))/(sumXsqN - (sumX)); //b
        intercept = (sumY - (slope * (sumX))/count); //a
        regPointOne = intercept + slope * firstValX;
        regPointTwo = intercept + slope * currValY;

        NSLog(@"pt1 %f pt2 %f", regPointOne, regPointTwo);
        
        

        //Draw Points (better way to do this?)
        if (nsArray == _MVO_D_Points) {

            CGContextSetFillColorWithColor(context, [UIColor yellowColor].CGColor);
            //CGContextFillEllipseInRect(context, CGRectMake(regPointOne-1.5, regPointTwo-1.5, 3, 3));
            CGContextFillEllipseInRect(context, CGRectMake(currValX-1.5, currValY-1.5, 3, 3));
            CGContextSetStrokeColorWithColor(context, [UIColor yellowColor].CGColor);
            
        }else if (nsArray == _MVO_U_Points){

            CGContextSetFillColorWithColor(context, [UIColor orangeColor].CGColor);
            CGContextFillEllipseInRect(context, CGRectMake(currValX-1.5, currValY-1.5, 3, 3));
            CGContextSetStrokeColorWithColor(context, [UIColor orangeColor].CGColor);
            
        }else if (nsArray == _TCP_D_Points){

            CGContextSetFillColorWithColor(context, [UIColor purpleColor].CGColor);
            CGContextFillEllipseInRect(context, CGRectMake(currValX-1.5, currValY-1.5, 3, 3));
            CGContextSetStrokeColorWithColor(context, [UIColor purpleColor].CGColor);
            
        }else{ //_TCP_U_Point

            CGContextSetFillColorWithColor(context, [UIColor redColor].CGColor);
            CGContextFillEllipseInRect(context, CGRectMake(currValX-1.5, currValY-1.5, 3, 3));
            CGContextSetStrokeColorWithColor(context, [UIColor redColor].CGColor);
            
        }
        
        CGContextBeginPath(context);
        CGContextMoveToPoint(context, prevValX, prevValY);
        //CGContextAddCurveToPoint(context, prevValX, prevValY, currValX, currValY, currValX, currValY);
        CGContextAddLineToPoint(context, currValX, currValY);
        CGContextSetLineJoin(context, kCGLineJoinRound);
        CGContextStrokePath(context);
    }
    
    //----- AXIS
    CGContextSetStrokeColorWithColor(context, [UIColor whiteColor].CGColor);
    CGContextBeginPath(context);
    
    //Vert Line
    CGContextMoveToPoint(context, 0, 0);
    CGContextAddLineToPoint(context, 0, 300);
    
    //Horiz Line
    CGContextMoveToPoint(context, 0, 300);
    CGContextAddLineToPoint(context, 300, 300);
    CGContextStrokePath(context); 
    //----- END AXIS
   }

@end