Minimization of a function in 3D
Code: "func_jmunuit_minimum2d.py"
Programming language: Python
http://jwork.org/dmelt/code/cache/func_jmunuit_minimum2d_3502.py
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``````
from java.lang import Math
from jhplot import *

class MyFunc(FNon):  # define a function a*(x-2)^2 + (y+1)^2
def value(self, x):
return (x[0]-2)*(x[0]-2)*self.p[0]+(x[1]+1)*(x[1]+1)

c1 = HPlot3D()                   # plot data and the fit function
c1.visible()
c1.setAutoRange()
pl = MyFunc("2D function",2,1) # 2 variables, 1 parameter
print pl.numberOfParameters()
print pl.dimension()
print pl.parameterNames().tolist()
pl.setParameter("par0",2)
print pl.parameters()
c1.draw( F2D(pl,-10,10,-10,10) ) # create plottable function and show it

from hep.aida.ref.optimizer.jminuit import *
op=JMinuitOptimizerFactory().create()
op.setFunction(pl)                                 # set function
op.variableSettings("x0").setValue(10)  # set initial value
op.variableSettings("x1").setValue(-10) # set initial value
op.optimize()                                         # perform optimization
res =op.result()
print "Minimization results=",res.parameters(), " status=",res.optimizationStatus()

``````