CPlotView:GetPtY

CPlotView:GetPtY

The GetY method returns the y value of a point in the class data matrix.

Syntax

y = CPlotView:GetPtY( n )

n is the index of the point in the data array.
y is the point y coordinate.
On success, this method returns the y coordinate.
On failure, this method returns 0.

Remarks

This method returns the y value of the specified point at index n. If n is out of range, the value 0 is returned. To remove ambiguity about whether the point truly has a value of 0 or is out of bounds, check the index before calling this method.

Example

The following script adds some points, then finds the nearest point and prints its x value:

P = CPlotView:new()	-- create a new CPlotView
P:Add( 11.82, 70.5, 10.25, 12.5)	-- add a point
P:Add( 4.62, 90.5, 11.5, 10.2)	-- add a point
n = P:FindPoint( 4, 72)	-- get index of point nearest 4,72
Printf("n=%d, y=%lg\n", n,P:GetPtY(n))	-- result: n = 1, y = 70.5