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A comparison of the convergence rates of Hestenes’ conjugate Gram-Schmidt method without derivatives with other numerical optimization methods Cover

A comparison of the convergence rates of Hestenes’ conjugate Gram-Schmidt method without derivatives with other numerical optimization methods

By: Md Nurul Raihen  
Open Access
|Jun 2024

Figures & Tables

Fig. 1

Level curves of Rosenbrock’s Banana Valley function.
Level curves of Rosenbrock’s Banana Valley function.

j_ijmce-2025-0010_tab_002

Step 1: restart: Digits:=50;
Step 2: f [1] := (x, y)− > 2 ∗ (x − 1) − 400 ∗ x(yxx);
Step 3: f [2] := (x, y)− > 200 ∗ (yxx);
Step 4: h := 0.001
Step 5: t[1] := 0; x1[1] := −1.2; x2[1] := 1.0;
Step 6: Perform the following iteration:
for i from 1 to 100 do
  for j from 1 to 2 do
k1[ j] := f [ j](x1[i], x2[i])
  end for:
  for j from 1 to 2 do
k2[ j] := f [ j](x1[i] + (h/2) ∗ k1[1], x2[i] + (h/2) ∗ k1[2])
  end for:
  for j from 1 to 2 do
k3[ j] := f [ j](x1[i] + (h/2) ∗ k2[1], x2[i] + (h/2) ∗ k2[2])
  end for:
  for j from 1 to 2 do
k4[ j] := f [ j](x1[i] + hk3[1], x2[i] + hk3[2])
  end for: x1[i + 1] := x1[i] + (h/6) ∗ (k1[1] + 2 ∗ k2[1] + 2 ∗ k3[1] + k4[1]):
x2[i + 1] := x2[i] + (h/6) ∗ (k1[2] + 2 ∗ k2[2] + 2 ∗ k3[2] + k4[2]):
t[i + 1] := t[i] + h
end for:
Step 7: print:
for i from 1 by 10 to 100 do print(t[i], x1[i], x2[i]);
end for;

j_ijmce-2025-0010_tab_003

Step 1: restart: Digits:=150;
Step 2: with(Student[LinearAlgebra]):
Step 3: Perform the following iteration:
x :=< −1.2, 1 >:
for i from 1 to 9 do
Jacobian :=< −400 ∗ (x[2] − x[1]2) + 800 ∗ x[1]2 + 2, −400 ∗ x[1], 200 >:
Jacobian(−1):
x := x − (Jacobian(−1)). < −400 ∗ x[1] ∗ x[2] + 400 ∗ x[1]3 + 2 ∗ (x[1] − 1), 200 ∗ (x[2] − x[1]2) >:
print(x[1], x[2]):
y[i, 1] := x[1];y[i, 2] = x[2];
end for

j_ijmce-2025-0010_tab_004

Step 1: restart: Digits:=50;
Step 2: gradient[1] := (x, y)− > 2 ∗ (x − 1) − 400 ∗ x(yxx);
Step 3: gradient[2] := (x, y)− > 200 ∗ (yxx);
Step 4: NORMofGRADIENT:=sqrt((2 ∗ (x − 1) − 400 ∗ x∗ (yxx))2 + (200 ∗ (yxx))2);
Step 5: NORMALIZED[1]:=(x,y)>(2*(1x)+400*x*(yx*x))sqrt((2*(x1)400*x*(yx*x))2+(200*(yx*x))2) {\rm{NORMALIZED}}[1]: = (x,y) - > \frac{{(2*(1 - x) + 400*x*(y - x*x))}}{{{\rm{sqrt}}({{(2*(x - 1) - 400*x*(y - x*x))}^2} + {{(200*(y - x*x))}^2})}} ;
Step 6: NORMALIZED[2]:=(x,y)>200*(x*xy)sqrt((2*(x1)400*x*(yx*x))2+(200*(yx*x))2) {\rm{NORMALIZED}}[2]: = (x,y) - > \frac{{200*(x*x - y)}}{{{\rm{sqrt}}({{(2*(x - 1) - 400*x*(y - x*x))}^2} + {{(200*(y - x*x))}^2})}} ;
Step 7: f[1]:=(x,y)>(2*(1x)+400*x*(yx*x))sqrt((2*(x1)400*x*(yx*x))2+(200*(yx*x))2) f[1]: = (x,y) - > \frac{{(2*(1 - x) + 400*x*(y - x*x))}}{{{\rm{sqrt}}({{(2*(x - 1) - 400*x*(y - x*x))}^2} + {{(200*(y - x*x))}^2})}}
Step 8: f[2]:=(x,y)>200*(x*xy)sqrt((2*(x1)400*x*(yx*x))2+(200*(yx*x))2) f[2]: = (x,y) - > \frac{{200*(x*x - y)}}{{{\rm{sqrt}}({{(2*(x - 1) - 400*x*(y - x*x))}^2} + {{(200*(y - x*x))}^2})}}
Step 9: h := 0.005
Step 10: t[1] := 0; x1[1] := −1.2; x2[1] := 1.0;
Step 11: Perform the following iteration:
for i from 1 to 100 do
  for j from 1 to 2 do
k1[ j] := f [ j](x1[i], x2[i])
  end for:
  for j from 1 to 2 do
k2[ j] := f [ j](x1[i] + (h/2) ∗ k1[1], x2[i] + (h/2) ∗ k1[2])
  end for:
  for j from 1 to 2 do
k3[ j] := f [ j](x1[i] + (h/2) ∗ k2[1], x2[i] + (h/2) ∗ k2[2])
  end for:
  for j from 1 to 2 do
k4[ j] := f [ j](x1[i] + hk3[1], x2[i] + hk3[2])
  end for: x1[i + 1] := x1[i] + (h/6) ∗ (k1[1] + 2 ∗ k2[1] + 2 ∗ k3[1] + k4[1]):
x2[i + 1] := x2[i] + (h/6) ∗ (k1[2] + 2 ∗ k2[2] + 2 ∗ k3[2] + k4[2]):
t[i + 1] := t[i] + h
end for:
Step 12: print:
for i from 1 by 10 to 100 do print(t[i], x1[i], x2[i]);
end for;

j_ijmce-2025-0010_tab_005

Step 1: restart: Digits:=400;
Step 2: sigma := 1e−120; rho := 2 ∗ sigma; epsilon := .1e−60;
Step 3: u[1, 1] := 1; u[1, 2] := 0; u[2, 1] := 0; u[2, 2] := 1;
Step 4: p[1, 1] := u[1, 1]; p[1, 2] := u[1, 2];
Step 5: f := (x1, x2) → 100 ∗ (x2x1)2 + (x1 − 1)2;
Step 6: x[1, 1] := −1.2; x[1, 2] := 1;
Step 7: Perform the following iteration:
for j from 1 to 10 do
c[1] := (f (x[1, 1]) − sigmap[1, 1], x[1, 2] − sigmap[1, 2]) − f (x[1, 1] + sigmap[1, 1], x[1, 2] + sigma
p[1, 2]))/(2 ∗ sigma):
d[1] := (f (x[1, 1] − sigmap[1, 1], x[1, 2] − sigmap[1, 2]) − 2 ∗ f (x[1, 1], x[1, 2]) + f (x[1, 1] + sigma
p[1, 1], x[1, 2] + sigmap[1, 2]))/(sigma)2
a[1] := c[1]/d[1]:
x[2, 1] := x[1, 1] + a[1] ∗ p[1, 1]:
x[2, 2] := x[1, 2] + a[1] ∗ p[1, 2]:
  for i for 1 to 2 do
x[2, i] := x[1, i] + a[1, i]
  end for:
c[2, 1] := (f (x[1, 1] + rhou[2, 1] − sigmap[1, 1], x[1, 2] + rhou[2, 2] − sigmap[1, 2]) − f (x[1, 1] + rho
u[2, 1] + sigmap[1, 1], x[1, 2] + rhou[2, 2] + sigmap[1, 2]))/(2 ∗ sigma):
a[2, 1] := c[2, 1]/d[1]:
b[2, 1] := (a[2, 1] − a[1])/rho:
  for i from 1 to 2 do
pbar[2, i] := u[2, i] + b[2, 1] ∗ p[1, i]
  end for:
  for i from 1 to 2 do
p[2, i] := pbar[2, i]/sqrt((pbar[2, 1])2 + (pbar[2, 2])2)
  end for:
  for k from 2 to 2 do
c[k] := (f (x[1, 1] − sigmap[k, 1], x[1, 2] − sigmap[k, 2]) − f (x[1, 1] + sigmap[k, 1], x[1, 2] + sigma
p[k, 2]))/(2 ∗ sigma)
  end for:
  for k from 2 to 2 do
d[k] := (f (x[1, 1] − sigmap[k, 1], x[1, 2] − sigmap[k, 2]) − 2 ∗ f (x[1, 1], x[1, 2]) + f (x[1, 1] + sigma
p[k, 1], x[1, 2] + sigmap[k, 2]))/(sigma)2
  end for:
  for k from 2 to 2 do
a[k] := c[k]/d[k]
  end for;
  for i from 1 to 2 do
x[3, i] := x[2, i] + a[2] ∗ p[2, i]
  end for;
  for i from 1 to 2 do
x[1, i] := x[3, i]
  end for;
print (x[3, 1], x[3, 2]);
y[ j, 1] := x[3, 1]; y[ j, 2] := x[3, 2];
end for

j_ijmce-2025-0010_tab_006

for i from 1 to 9 do
  C[i] = sqrt((y[i + 1, 1] − 1)2 + (y[i + 1, 2] − 1)2)/(sqrt((y[i, 1] − 1)2 + (y[i, 2] − 1)2));
end for;

The asymptotic constants of a nonlinear function_

Asymptotic ConstantCGS methodNewton methodSteepest Descent methodRunge-Kutta method

C10.8574850.8574850.4535890.785244
C20.0274250.0274250.4545440.785678
C30.2433580.2433580.4555020.786108
C40.0030720.0030720.4564630.786534
C50.2000030.2000030.4574280.786955
C60.0030730.0030730.4583960.787372
C70.2000020.2000020.4593670.787783
C80.0030730.0030730.4603410.788190
Language: English
Page range: 111 - 124
Submitted on: Sep 26, 2023
Accepted on: Feb 12, 2024
Published on: Jun 3, 2024
Published by: Harran University
In partnership with: Paradigm Publishing Services
Publication frequency: 2 issues per year

© 2024 Md Nurul Raihen, published by Harran University
This work is licensed under the Creative Commons Attribution 4.0 License.