Пример. Решение системы ОДУ первого порядка

Функции > Решение и оптимизация > Функции блока решения > Пример. Решение системы ОДУ первого порядка

Используйте блок решения и функцию odesolve для решения системы обыкновенных дифференциальных уравнений первого порядка.

1. Задайте конечную точку интервала решения

2. Определите задачу, используя производные и набор начальных приближений:

Щелкните для копирования этого выражения

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3. Постройте график решения на одном интервале:

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Использование функции Rkadapt

Используйте функцию Rkadapt для решения этой же системы дифференциальных уравнений.

1. Задайте функцию, которая определяет вектор значений производной в любой точке решения (t,Y):

2. Задайте дополнительные аргументы для решателя ОДУ:

a. Начальное значение независимой переменной

b. Вектор начальных значений функции

c. Количество значений решения на интервале [t0, t1]

3. Используйте функцию Rkadapt для нахождения матрицы решения:

Можно также использовать функции rkfixed, Bulstoer или Radau.

4. Извлеките значения независимой переменной

5. Извлеките значения первой функции решения

6. Извлеките значения второй функции решения

7. Извлеките значения третьей функции решения

8. Постройте графики всех трех решений:

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График решения odesolve почти совпадает с графиком решения Rkadapt.

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