Before solving your system of ordinary differential equations you need to program
it in Runge. This section describes the way you can do that.
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1.
- Choose type of your system:
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2.
- Choose dimension:
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3.
- Choose independent variable. It should be valid identifier (i.e. a string
beginning with letter):
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4.
- Enter the system you’d like to solve. First column is for dependent
variables (valid identifiers, i.e. strings beginning with letter), second
one is for equations. Equations should be valid expressions containing
arithmetic operators and elementary functions. You can also use macros
(like macro “p” shown below) for repeating expressions:
The following system is entered at this picture:
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1.
- Choose solver. Not every solver works for a given system type:
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2.
- Set start parameters, values and macros:
Here you can set:
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1.
- Click Start button to start solving the system. For big
systems or long time ranges you might see progress bar
Here you can stop, pause and resume solving process by using
appropriate buttons.
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2.
- Explore solution
Every solution has an id starting from zero.
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3.
- Explore solution graphically (here you can select different variables for
X and Y axes):
Use Export feature to export solution to other programs like MS Excel or
MATLAB
Excel should read it like this:
MATLAB should read it like this:
And after issuing a command like
>> plot(solution0(:,2), solution0(:,3));
it should render a plot: