plain ==================
result =  1.412209
sigma  =  0.013436
exact  =  1.393204
error  =  0.019005 = 1.4 sigma
miser ==================
result =  1.391322
sigma  =  0.003461
exact  =  1.393204
error  = -0.001882 = 0.54 sigma
vegas warm-up ==================
result =  1.392673
sigma  =  0.003410
exact  =  1.393204
error  = -0.000531 = 0.16 sigma
converging...
result =  1.393281 sigma =  0.000362 chisq/dof = 1.5
vegas final ==================
result =  1.393281
sigma  =  0.000362
exact  =  1.393204
error  =  0.000077 = 0.21 sigma