How to find the Axis Scale ticks range?

With the need of draw a line on y axis, from 0 to max tick.

Drawing an log scale, Is there a way to identify the last tick value - if so can draw the line unto that !.

See https://plot.ly/javascript/reference/#layout-yaxis-tick0

Thanks for the response.

I am in need of fetching the scale range, I see range property to specify the range.

To give more details:
Drawing an Logarithmic scale on y axis, as based on the given input of the Y - the scale range changing dynamically. As and when Y value reaches thresholds - need to draw an marker (triangle).

With this need, need to find the Y axis scale low and high values - So I can specify the marker’s position.