#
# File:
# fillxy1.py
#
# Synopsis:
# Illustrates how to fill between curves in an XY plot.
#
# Categories:
# xy plots
#
# Author:
# Mary Haley
#
# Date of initial publication:
# August 2010, based on NCL example
#
# Description:
# This example shows how to set a resource for filling between XY curves.
#
# Effects illustrated:
# o Filling the area between two curves in an XY plot
# o Subscripting a variable using coordinate values
# o Using indexed color.
#
# Output:
# A single visualization with two XY curves
#
import numpy,os
import Ngl,Nio
dirc = Ngl.pynglpath("data")
f = Nio.open_file(os.path.join(dirc,"cdf","uv300.nc"))
u = f.variables["U"]
lat = f.variables["lat"][:]
#---To plot multiple lines, you must put them into a multi-dimensional array.
data = numpy.zeros([2,len(lat)],'f')
data[0,:] = u['time|i0 lat|: lon|82']
data[1,:] = u['time|i0 lat|: lon|-69']
#---Start the graphics section
wks_type = "png"
wks = Ngl.open_wks (wks_type,"fillxy1") # Open "fillxy1.png" PNG file.
#---Set some resources.
res = Ngl.Resources()
res.tiMainString = "Filling between two curves"
res.nglXYAboveFillColors = 100 # Indexes into the current color table.
res.nglXYBelowFillColors = 184 # Could also use named colors, e.g. "red"
res.xyLabelMode = "Custom" # Custom label the curves
res.xyExplicitLabels = ['Y1','y2']
plot = Ngl.xy (wks,lat,data,res) # Draw plot
Ngl.end()