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meteorgan
(define(general-solve-2nd f y0 dy0 dt) (define y (integral (delay dy) y0 dt)) (define dy (integral (delay ddy) dy0 dt)) (define ddy (stream-map f dy y)) y)
Eva Lu Ator
The first argument to f should be dy/dt rather than dy. Therefore we have
(define (solve-2nd-general f dt y0 dy0) (define y (integral (delay dy) y0 dt)) (define dy (integral (delay ddy) dy0 dt)) (define ddy (stream-map f (scale-stream dy (/ 1.0 dt)) y)) y)
(define(general-solve-2nd f y0 dy0 dt) (define y (integral (delay dy) y0 dt)) (define dy (integral (delay ddy) dy0 dt)) (define ddy (stream-map f dy y)) y)Eva Lu Ator
The first argument to f should be dy/dt rather than dy. Therefore we have
(define (solve-2nd-general f dt y0 dy0) (define y (integral (delay dy) y0 dt)) (define dy (integral (delay ddy) dy0 dt)) (define ddy (stream-map f (scale-stream dy (/ 1.0 dt)) y)) y)