i want to write matlab code for x(i+1) = x(i) + 0.05*2*x(i), i=0:0.05:1, x(0) =2

i want to write matlab code for

x(i+1) = x(i) + 0.05*2*x(i),  i=0:0.05:1, x(0) =2

how can i do it in matlab?

[Stephen23]

This will not work:

x(i+1) = x(i) + 0.05*2*x(i),  i=0:0.05:1

The vector i contains fraction values and it is shown as an index into x. Indices must be integer or logical, so using a fractional value will throw an error.

What have you tried so far? Please show us your code attempt.

[Ali Asghar]

Thank for reply. I just started this work and having problem in inner loop in writing formula.

I wrote this code till yet.

clc, clear all, close all 
T = 0.05;
for i=0:1:19;
    for j = 1:1:20
        x(i,j) =  ???
    end 
end

Answer 1

[Stephen23]

Perhaps one of these does what you want:

>> i = 0:0.05:1;
>> x = cumsum(2+0.05*2*i)
x =
  2.0000    4.0050    6.0150    8.0300   10.0500   12.0750   14.1050   16.1400   18.1800   20.2250   22.2750   24.3300   26.3900   28.4550   30.5250   32.6000   34.6800   36.7650   38.8550   40.9500   43.0500
>> x = 2+cumsum(0.05*2*i)
x =
  2.0000   2.0050   2.0150   2.0300   2.0500   2.0750   2.1050   2.1400   2.1800   2.2250   2.2750   2.3300   2.3900   2.4550   2.5250   2.6000   2.6800   2.7650   2.8550   2.9500   3.0500

[Ali Asghar]

dear this code not working. actual answer are x(0) = 2, x(1) = 2.2, x(2) = 2.42, x(3) = 2.662...........

[Stephen23]

>> 2*1.1.^(0:10)
ans =
     2.0000   2.2000   2.4200   2.6620   2.9282   3.2210   3.5431   3.8974   4.2872   4.7159   5.1875

Please remember to accept my answer if this helps you.

[Ali Asghar]

Thank you soo much

Answer 2

[ARAVIND]

ii = [0:0.05:1]; X = zeros(1,numel(ii)); X(1) = 2; for cnt = 1:numel(ii) X(cnt) = X(cnt)+ 0.05*2*ii(cnt); end

[ARAVIND]

Hello Stephen, Thank you for your simpler answer. Can you explain the your code. I want to modify your code for different value(0.06 instead of 0.05).

Kind Regards, Aravind

[Stephen23]

x0 = 2;
fr = 0.06;
x0*(1+2*fr).^(0:10)