ode15s — Solve stiff ordinary differential equations with an adaptive implicit host-side integrator.
ode15s integrates stiff first-order ODE systems y' = f(t, y) using adaptive implicit stepping. For two outputs, it returns [t, y] where each row of y corresponds to one time in t.
How ode15s works
- Supports scalar, vector, and matrix-valued initial conditions.
- Accepts options as a struct, including
RelTol,AbsTol,InitialStep, andMaxStep. - When
tspanhas more than two points, the solver returns values at each requested time. - With one output, returns only the
ytrajectory matrix.
Example
Integrate a stiff scalar decay system
[t, y] = ode15s(@(t, y) -15*y, [0 1], 1)Expected output:
y(end) is small and positiveRelated Math functions
Elementwise
abs · angle · conj · double · exp · expm1 · factorial · gamma · hypot · imag · ldivide · log · log10 · log1p · log2 · minus · nextpow2 · plus · pow2 · power · rdivide · real · sign · single · sqrt · times
Trigonometry
acos · acosh · asin · asinh · atan · atan2 · atanh · cos · cosh · sin · sinh · tan · tanh
Reduction
all · any · cummax · cummin · cumprod · cumsum · cumtrapz · diff · gradient · max · mean · median · min · nnz · prod · std · sum · trapz · var
Structure
Open-source implementation
Unlike proprietary runtimes, every RunMat function is open-source. Read exactly how ode15s works, line by line, in Rust.
- View ode15s.rs on GitHub
- Learn how the runtime works
- Found a bug? Open an issue with a minimal reproduction.
About RunMat
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