Question: I'm working with data (stuff like Sin/Cosin waves, etc) that repeat with frequency M.
I've written a simple display control where it takes the data and paints connected lines to represent the data in a pretty picture.

My question is, the data is given where if painted onto a bitmap, quadrant 1 data is in quadrant 3 and quadrant 2 data is in quadrant 4 (and vice versa).

The bitmap is of width M and hight `array.Max - array.Min`.

Is there a simple transform for changing the data so it will display in the appropriate quadrants?

Answer: 
A good way of thinking about it is that (0,0) in world coordinates is divided between 

`(0,0), (width, 0), (0,height), (width, height)`

which would (width/2, height/2) in image coordinates.

From there, the transform would be:

```
Data(x,y) => x = ABS(x - (width/2)), y = ABS(y - (Height/2))

```
Try to invert the y-axis using

```
g.ScaleTransform(1, -1);

```