# This example shows how to plot X-Y using Waterloo with error bars

from kcl.waterloo.swing import GCFrame
from kcl.waterloo.graphics import GJGraph,GJGraphContainer
from kcl.waterloo.graphics.plots2D import GJErrorBar,GJPlotInterface
import math

f=GCFrame()
gc=GJGraphContainer.createInstance(GJGraph.createInstance())
f.add(gc)

# show sqrt(x*x) with error bars
x=[]
y=[]
err=[]
for i in range(10):
      x.append(i*4)
      y.append(math.sqrt(i*i))
      err.append(2)
p=GJErrorBar.createInstance()
p.setXData(x)
p.setYData(y)
p.setExtraData0(err) # right error
p.setExtraData1(err) # upper error 
p.setExtraData2(err) # left error
p.setExtraData3(err) # lower error 
gc.getView().add(p)
gc.getView().autoScale()

print "Creating SVG image.."
from kcl.waterloo.export import ExportFactory
from java.io import File
ExportFactory.saveAsSVG(gc, File("canvas2D_errors_waterloo.svg"))