Can you help me draw the plot with decimals?

clear;
clc;
k=0.7944;
firstone=2;
carry=64;
syms f(y)
syms y
f(y)=k*y*(carry-y)

f(y) = 

endday=0.1;
dt=0.01;
    n=endday/dt;
    i=1;
for i=1:n
    xia=i*dt;
    yi=f(xia);
    I1(i/n)=(1/(1-yi*dt))^(i)*firstone;
end

Array indices must be positive integers or logical values.

Error in sym/privsubsasgn (line 1307)
L_tilde2 = builtin('subsasgn',L_tilde,struct('type','()','subs',{varargin}),R_tilde);

Error in indexing (line 1138)
C = privsubsasgn(L,R,inds{:});

dt=0.001;
    k=endday/dt;
    i=1;
for i=1:k
    xib=i*dt;
    yi=f(xib);
    I2(i/k)=(1/(1-yi*dt))^(i)*firstone;
end

figure(1)
plot(I1)
figure(2)
plot(I2)

Arrays must be indexed by int values. But I have to draw the plot with decimals. Please help.

[Jan]

What exactly is your question? What does this mean: "Arrays must be indexed by int values."? Is this a paraphrased error message? If so, please post a copy of the message instead.

I've edited your question and pressed the Run button, such that the error message is displayed.

Answer 1

[Jan]

I1(i/n) = ...    

This cannot work. i/n is not an integer and therefore not possible as index. Remember what indices are: X(k) addresses the k.th element of the vector X. So what should I1(i/n) be?

The solution is easy: Use I1(i) instead. If you need to define the X values with a fractional part in the plot, define the X values of the plot accordingly:

% plot(I1)  ==>
plot((1:n) / n, I1)

Note:

i=1;  % <== Useless, because i is overwritten in the next line:
for i=1:n

[seoung gi Sin]

thank you