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import math
import unittest
import IECore

class LevenbergMarquardtTest( unittest.TestCase ) :

	class Fn( IECore.LevenbergMarquardtd.ErrorFn ) :

		def __init__( self ) :

			IECore.LevenbergMarquardtd.ErrorFn.__init__( self )

		def numErrors( self ) :

			return 10

		def computeErrors( self, parameters, errors ) :

			for i in range( 0, self.numErrors() ) :

				errors[i] = math.fabs(
					math.pow( i, parameters[0] ) -
					math.pow( i, 2.0 )
				)

	# Simple test of binding. More complete tests present in C++ test suite.
	def test( self ) :

		lm = IECore.LevenbergMarquardtd()

		parameters = IECore.DoubleVectorData()
		parameters.append( 1.0 )

		fn = LevenbergMarquardtTest.Fn()

		lm.solve( parameters, fn )

		self.assertAlmostEqual( parameters[0], 2.0 )

if __name__ == "__main__":
    unittest.main()

