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--- libnum:examples:gear [2026/03/04 14:06] – abc
+++ libnum:examples:gear [Unknown date] (current) – removed - external edit (Unknown date) 127.0.0.1
@@ Line 1: / Line 1: @@
-====== Integration of Systems of Linear Differential Equations ======
-Gear Method.\\
-Let's examine the following //SLDE//:
-  y₁′ = y₂
-  y₂′ = y₁
-  y₁(0)=0  and  y₂(0)=1
-  # we expect sin(x)/cos(x) as the result
-<file>
-#include <stdio.h>
-#include <math.h>
-#include "libnum/gear.h"
-using namespace NumericMethods;
-{
- double initValues[] = { 0, 1, 0, 0};
- GearUserProc uf1(diffun1), uf2(j1);
- Gear solver;
- solver.set(2, &uf1, &uf2); // task dimention is 2
- GearAssistant& assistant = solver.assistant;
- assistant.params.setParameter("HINI", 0.0001);  // starting step of integration
- assistant.params.setParameter("EPS", 0.001);    // step error constant
- GearEngineCallbackEmbed printHandler(my_print);
- solver.setCallback(printHandler);
- try
- {
-  Message rc=solver.solve(0, 5, initValues);     // integrate for t from 0 to 5
- }
- catch(Message e) {}
-}
-</file>