code: func (f *Fpdf) TransformScaleY(scaleHt, x, y float64) {
  	f.TransformScale(100, scaleHt, x, y)
  }
docs: // TransformScaleY scales the height of the following text, drawings and
  // images. scaleHt is the percentage scaling factor. (x, y) is center of
  // scaling.
  //
  // The TransformBegin() example demonstrates this method.