How to draw line chart with smooth curve in iOS? -

i have points (x1,y1), (x2,y2), (x3,y3)...

now want draw chart smooth curve?

i'm trying draw below

-(void)drawprices {     nsinteger count = self.prices.count;      uibezierpath *path = [uibezierpath bezierpath];      path.linecapstyle = kcglinecapround;      for(int i=0; i<count-1; i++)     {         cgpoint controlpoint[2];          cgpoint p = [self pointwithindex:i indata:self.prices];         if(i==0)         {             [path movetopoint:p];         }          cgpoint nextpoint, previouspoint, m;         nextpoint = [self pointwithindex:i+1 indata:self.prices];         previouspoint = [self pointwithindex:i-1 indata:self.prices];          if(i > 0) {             m.x = (nextpoint.x - previouspoint.x) / 2;             m.y = (nextpoint.y - previouspoint.y) / 2;         } else {             m.x = (nextpoint.x - p.x) / 2;             m.y = (nextpoint.y - p.y) / 2;         }          controlpoint[0].x = p.x + m.x * 0.2;         controlpoint[0].y = p.y + m.y * 0.2;          // second control point         nextpoint = [self pointwithindex:i+2 indata:self.prices];         previouspoint = [self pointwithindex:i indata:self.prices];         p = [self pointwithindex:i + 1 indata:self.prices];         m = zeropoint;          if(i < self.prices.count - 2) {             m.x = (nextpoint.x - previouspoint.x) / 2;             m.y = (nextpoint.y - previouspoint.y) / 2;         } else {             m.x = (p.x - previouspoint.x) / 2;             m.y = (p.y - previouspoint.y) / 2;         }          controlpoint[1].x = p.x - m.x * 0.2;         controlpoint[1].y = p.y - m.y * 0.2;          [path addcurvetopoint:p controlpoint1:controlpoint[0] controlpoint2:controlpoint[1]];     }      cashapelayer *linelayer = [cashapelayer layer];     linelayer.path = path.cgpath;     linelayer.linewidth = line_width;     linelayer.strokecolor = _pricecolor.cgcolor;     linelayer.fillcolor = [uicolor clearcolor].cgcolor;      [self.layer addsublayer:linelayer]; } 

but in situation, line "go back"

is there better way that?

i find answer @ draw graph curves uibezierpath

and try implement code

+ (uibezierpath *)quadcurvedpathwithpoints:(nsarray *)points {     uibezierpath *path = [uibezierpath bezierpath];      nsvalue *value = points[0];     cgpoint p1 = [value cgpointvalue];     [path movetopoint:p1];      if (points.count == 2) {         value = points[1];         cgpoint p2 = [value cgpointvalue];         [path addlinetopoint:p2];         return path;     }      (nsuinteger = 1; < points.count; i++) {         value = points[i];         cgpoint p2 = [value cgpointvalue];          cgpoint midpoint = midpointforpoints(p1, p2);         [path addquadcurvetopoint:midpoint controlpoint:controlpointforpoints(midpoint, p1)];         [path addquadcurvetopoint:p2 controlpoint:controlpointforpoints(midpoint, p2)];          p1 = p2;     }     return path; }  static cgpoint midpointforpoints(cgpoint p1, cgpoint p2) {     return cgpointmake((p1.x + p2.x) / 2, (p1.y + p2.y) / 2); }  static cgpoint controlpointforpoints(cgpoint p1, cgpoint p2) {     cgpoint controlpoint = midpointforpoints(p1, p2);     cgfloat diffy = abs(p2.y - controlpoint.y);      if (p1.y < p2.y)         controlpoint.y += diffy;     else if (p1.y > p2.y)         controlpoint.y -= diffy;      return controlpoint; } 

thanks user1244109 ^_^.