import ROOT,argparse

parser=argparse.ArgumentParser(description='check if error propagates correct')
parser.add_argument('--padSize',help='size in X and Y of pad',type=float,default=[1,1])

args=parser.parse_args()

xVec=ROOT.RooArgList()
muVec=ROOT.RooArgList()
cov=ROOT.TMatrixDSym(2)

for i in range(2):
    name='pos'+str(i)
    xvar=ROOT.RooRealVar(name,name,0,-10*args.padSize[i],+10*args.padSize[i])
    xVec.add(xvar)
    name='mu'+str(i)
    muvar=ROOT.RooRealVar(name,name,0,-10*args.padSize[i],+10*args.padSize[i])
    muVec.add(muvar)
    cov[i][i]=1

cov.Print()

mvgGen=ROOT.RooMultiVarGaussian("mvgGen","mvgGen",xVec,muVec,cov)