Make object RectTransform in height as width

I'm trying to make a responsive square by code, I want to make the height as the width. my try is

``` RectTransform myRect = GetComponent(typeof(RectTransform)) as RectTransform;

     //If you want the middle of the rect be somewhere else then the middle of the screen change it here (0 ... 1, 0 ... 1)
     Vector2 rectMiddle = new Vector2(0.5f, 0.7f);

     float horizontalSize = 1f; //50% of horizontal screen used
     float verticalSize = 0.5f; //75%  of vertical screen used

     myRect.sizeDelta = Vector2.zero;
     myRect.anchoredPosition = Vector2.zero; 

     myRect.anchorMin = new Vector2(rectMiddle.x - horizontalSize / 2, rectMiddle.x - verticalSize / 2);
     myRect.anchorMax = new Vector2(rectMiddle.x + horizontalSize / 2, rectMiddle.x - verticalSize / 2);

```