Okay you got me, what is a semi discretization?

]]>Do you have some initial conditions for post#1. If I have initial conditions I might be able to.

]]>I am already stuck on how he derived:

]]>I have the 1999 edition. My pahe 50 has a figure 2.12 on the top. Am I in the right spot?

]]>so please.. help me dude..

]]>I have that book, please tell me where in it are you exactly working! Maybe I can help out.

]]>my exercise is to analyze the fixed point stability from discrete time epidemic model.but the model on that book can't be anlyzed, so i think to change from the continuous model to discrete model.. i'm so thankful..

]]>I am a little confused here. As far as I know you can convert a DE ( continuous ) into a Recurrence ( discrete ), you don't convert the constants. I don't understand what you are trying to accomplish. Can you give more? What textbook or webpage are you studying from?

]]>ex :

dS/dt = (alpha)*n- (alpha)*S - (beta)*S*I

dI/dt = (beta)*S*I- (gamma)*I

dR/dt = (gamma)*I

become

S = ??

I = ??

R =??

thank you very much...

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