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Added Levenberg-Marquardt algorithm and svd Golub-Kahan #513

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margarita0303 merged 35 commits from dev into dev 2023-06-19 16:11:59 +03:00
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2 changed files with 33 additions and 35 deletions
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66
kmath-tensors/src/commonMain/kotlin/space/kscience/kmath/tensors/core/LevenbergMarquardtAlgorithm.kt
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@ -7,7 +7,6 @@ package space.kscience.kmath.tensors.core
import space.kscience.kmath.linear.transpose
import space.kscience.kmath.nd.*
import space.kscience.kmath.tensors.api.LinearOpsTensorAlgebra
import space.kscience.kmath.tensors.core.BroadcastDoubleTensorAlgebra.div
import space.kscience.kmath.tensors.core.BroadcastDoubleTensorAlgebra.dot
import space.kscience.kmath.tensors.core.BroadcastDoubleTensorAlgebra.minus
@ -19,11 +18,26 @@ import kotlin.math.min
import kotlin.math.pow
import kotlin.reflect.KFunction3
/**
* Type of convergence achieved as a result of executing the Levenberg-Marquardt algorithm
*
* InGradient: gradient convergence achieved
* (max(J^T W dy) < epsilon1 = opts[2],
* where J - Jacobi matrix (dy^/dp) for the current approximation y^,
* W - weight matrix from input, dy = (y - y^(p)))
* InParameters: convergence in parameters achieved
* (max(h_i / p_i) < epsilon2 = opts[3],
* where h_i - offset for parameter p_i on the current iteration)
* InReducedChiSquare: chi-squared convergence achieved
* (chi squared value divided by (m - n + 1) < epsilon2 = opts[4],
* where n - number of parameters, m - amount of points
* NoConvergence: the maximum number of iterations has been reached without reaching convergence
*/
public enum class TypeOfConvergence{
inRHS_JtWdy,
inParameters,
inReducedChi_square,
noConvergence
InGradient,
InParameters,
InReducedChiSquare,
NoConvergence
}
public data class LMResultInfo (
@ -37,6 +51,12 @@ public data class LMResultInfo (
var epsilon: Double
)
public data class LMSettings (
var iteration:Int,
var func_calls: Int,
var example_number:Int
)
public fun DoubleTensorAlgebra.lm(
func: KFunction3<MutableStructure2D<Double>, MutableStructure2D<Double>, LMSettings, MutableStructure2D<Double>>,
p_input: MutableStructure2D<Double>, t_input: MutableStructure2D<Double>, y_dat_input: MutableStructure2D<Double>,
@ -44,7 +64,7 @@ public fun DoubleTensorAlgebra.lm(
c_input: MutableStructure2D<Double>, opts_input: DoubleArray, nargin: Int, example_number: Int): LMResultInfo {
val resultInfo = LMResultInfo(0, 0, example_number, 0.0,
0.0, p_input, TypeOfConvergence.noConvergence, 0.0)
0.0, p_input, TypeOfConvergence.NoConvergence, 0.0)
val eps:Double = 2.2204e-16
@ -299,15 +319,6 @@ public fun DoubleTensorAlgebra.lm(
if (prnt > 1) {
val chi_sq = X2 / DoF
// println("Iteration $settings | chi_sq=$chi_sq | lambda=$lambda")
// print("param: ")
// for (pn in 0 until Npar) {
// print(p[pn, 0].toString() + " ")
// }
// print("\ndp/p: ")
// for (pn in 0 until Npar) {
// print((h.as2D()[pn, 0] / p[pn, 0]).toString() + " ")
// }
resultInfo.iterations = settings.iteration
resultInfo.func_calls = settings.func_calls
resultInfo.result_chi_sq = chi_sq
@ -319,42 +330,29 @@ public fun DoubleTensorAlgebra.lm(
// cvg_hst(iteration,:) = [ func_calls p' X2/DoF lambda ];
if (abs(JtWdy).max()!! < epsilon_1 && settings.iteration > 2) {
// println(" **** Convergence in r.h.s. (\"JtWdy\") ****")
// println(" **** epsilon_1 = $epsilon_1")
resultInfo.typeOfConvergence = TypeOfConvergence.inRHS_JtWdy
resultInfo.typeOfConvergence = TypeOfConvergence.InGradient
resultInfo.epsilon = epsilon_1
stop = true
}
if ((abs(h.as2D()).div(abs(p) + 1e-12)).max() < epsilon_2 && settings.iteration > 2) {
// println(" **** Convergence in Parameters ****")
// println(" **** epsilon_2 = $epsilon_2")
resultInfo.typeOfConvergence = TypeOfConvergence.inParameters
resultInfo.typeOfConvergence = TypeOfConvergence.InParameters
resultInfo.epsilon = epsilon_2
stop = true
}
if (X2 / DoF < epsilon_3 && settings.iteration > 2) {
// println(" **** Convergence in reduced Chi-square **** ")
// println(" **** epsilon_3 = $epsilon_3")
resultInfo.typeOfConvergence = TypeOfConvergence.inReducedChi_square
resultInfo.typeOfConvergence = TypeOfConvergence.InReducedChiSquare
resultInfo.epsilon = epsilon_3
stop = true
}
if (settings.iteration == MaxIter) {
// println(" !! Maximum Number of Iterations Reached Without Convergence !!")
resultInfo.typeOfConvergence = TypeOfConvergence.noConvergence
resultInfo.typeOfConvergence = TypeOfConvergence.NoConvergence
resultInfo.epsilon = 0.0
stop = true
}
} // --- End of Main Loop
}
return resultInfo
}
public data class LMSettings (
var iteration:Int,
var func_calls: Int,
var example_number:Int
)
/* matrix -> column of all elemnets */
public fun make_column(tensor: MutableStructure2D<Double>) : MutableStructure2D<Double> {
val shape = intArrayOf(tensor.shape.component1() * tensor.shape.component2(), 1)
@ -564,7 +562,7 @@ public fun lm_FD_J(func: (MutableStructure2D<Double>, MutableStructure2D<Double>
}
}
p[j, 0] = ps[j, 0] // restore p(j)
p[j, 0] = ps[j, 0]
}
return J.as2D()

2
kmath-tensors/src/commonTest/kotlin/space/kscience/kmath/tensors/core/TestLmAlgorithm.kt
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@ -134,7 +134,7 @@ class TestLmAlgorithm {
assertEquals(1, result.example_number)
assertEquals(0.9131368192633, (result.result_chi_sq * 1e13).roundToLong() / 1e13)
assertEquals(3.7790980 * 1e-7, (result.result_lambda * 1e13).roundToLong() / 1e13)
assertEquals(result.typeOfConvergence, TypeOfConvergence.inParameters)
assertEquals(result.typeOfConvergence, TypeOfConvergence.InParameters)
val expectedParameters = BroadcastDoubleTensorAlgebra.fromArray(
ShapeND(intArrayOf(4, 1)), doubleArrayOf(20.527230909086, 9.833627103230, 0.997571256572, 50.174445822506)
).as2D()