# Simulation of rate equation

by almesba
Tags: equation, rate, simulation
 P: 5 i have try this rate equation code in MATLAB. but its not working. can anyone help me please!!!!! mm=0; for I = 0.1e-3:0.1e-3:4.5e-3; m=mm+1; q=1.6e-19; alpha=2; Tn=3e-9; Tp=1e-12; G0=0.6; N0 = 1e24; Gamma=.2; epsilon=1e1; Va=3.7e-14; tini=0; tfin=4e-9; dt=1e-12; N(1)=0; S(1)=0; p=G0*N(m)*S(m); l=1+epsilon*S(m); y=q*Va; for t=tini:dt:tfin delN=(I/y)-(N(m)/Tn)-(p/l); end end tt=t; tt=tt*1e9; figure(1); plot(tt,N);
 P: 120 I'm not sure whether Matlab requires that you define your variables before attempting to execute them, but I see that line 4, for example, (I0 = N0*q*Va/Tn;) contains several variables you do not define until later in your routine.
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P: 40,717
 Quote by almesba i have try this rate equation code in MATLAB. but its not working. can anyone help me please!!!!! mm=0; for I = 0.1e-3:0.1e-3:4.5e-3; m=mm+1; q=1.6e-19; alpha=2; Tn=3e-9; Tp=1e-12; G0=0.6; N0 = 1e24; Gamma=.2; epsilon=1e1; Va=3.7e-14; tini=0; tfin=4e-9; dt=1e-12; N(1)=0; S(1)=0; p=G0*N(m)*S(m); l=1+epsilon*S(m); y=q*Va; for t=tini:dt:tfin delN=(I/y)-(N(m)/Tn)-(p/l); end end tt=t; tt=tt*1e9; figure(1); plot(tt,N);
Welcome to the PF. What do you mean by "not working"? Does MATLAB throw an error somewhere, or does the program run and not give a reasonable answer?

P: 5
Simulation of rate equation

 Quote by berkeman Welcome to the PF. What do you mean by "not working"? Does MATLAB throw an error somewhere, or does the program run and not give a reasonable answer?
MATLAB isnt throwing any error. NOT WORKING means i am getting a white or blank graph. i have tried with different axis values but still no result.
 Sci Advisor P: 2,751 p=G0*N(m)*S(m); l=1+epsilon*S(m) Both those lines are bound to throw an error on the second iteration because neither N() or S() are defined past an index of 1.

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