using euler method for population growth

Question

Kelsey Pettrone 2020-9-21

回答： Alan Stevens 2020-9-21

I dont know how i would write this formula using the euler method

dp/dt=G(Pmax-P(t))*p(t)

Plot the population as a function of time from t = 0 to t = 20 years

Use the following values for constants in the differential equation: o pmax = 10,000 o G = 0.00005

Use an initial condition of p = 800 when t=0

Walter Roberson 2020-9-21

Is P(t) different than p(t) ?

I recommend you look at ode45()

Reminder: MATLAB has no implied multiplication. All multiplication needs to be explicit with either .* or *

James Tursa 2020-9-21

What have you done so far? What specific problems are you having with your code?

Answer 1

Alan Stevens 2020-9-21

If you must use the simple Euler method you need to write the equation in the following form:

p(i+1) = p(i) + dt*G*(pmax - p(i))*p(i);

where dt is your chosen timestep size, and i loops from 2 to N, where N is 20/dt. You would first set p(1) = 800.