WhenEvent

WhenEvent[event, action] specifies an action that occurs when the event triggers it for equations in NDSolve and related functions.

Examples

NDSolve[{y'[t] == y[t], y[0] == 1, WhenEvent[y[t] > 2, "StopIntegration"]}, y, {t, 0, 5}]

sol = NDSolve[{x''[t] == -x[t], x[0] == 1, x'[0] == 0, WhenEvent[x[t] == 0, x'[t] -> -0.9 x'[t]]}, x, {t, 0, 20}]

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