Adds a polyline to an existing plot.
pline = Ngl.add_polyline(wks, plot, x, y, res=None)
The identifier returned from calling Ngl.open_wks.plot
The id of the plot which you want to add the polylines to.x, y
One-dimensional (masked) NumPy arrays or Python lists containing the x, y coordinates of the polyline.res=None
An (optional) instance of the Resources class having GraphicStyle resources as attributes.
A PlotId representing the polyline added.
This function adds a polyline to the requested plot. plot is the value returned from a previous call to one of the PyNGL plotting functions, like Ngl.xy, Ngl.contour_map, etc. x and y are 1-dimensional arrays (these can be Python lists or tuples, or NumPy arrays) defining the coordinates of the polyline, and resources can optionally contain an unlimited number of attributes that are GraphicStyle resource names and their values. Note that x and y must be in the same data space as the data in plot.
Note: unlike Ngl.polyline, this function does not actually draw the polyline. It only attaches a polyline to the given plot. You need to call Ngl.draw on plot in order to see the plot with the line added.
If you call this function multiple times, you should use a unique variable to hold the id returned.