Decrementing step for loop I matlab

y = zeros(1,12);
 for i = 1:12
 y(i+1) = y(i) + ((5 - (4/50)*y(i)));
 end
 y
 x = zeros(1,10);
 for i = 10:-1:2
 x(i-1) = x(i) + ((5 + (4/50)*x(i)));
 end
 x

Good Day,

May I ask how can I insert the start and stop variable on above code? for example I want to start in 17 to 30 or 15 to 2 with decrementing step.

Thanks and Regards,

Dennis

Answer 1

[Awais Saeed]

% start, step, and end points
starty = 1;
endy = 12;
startx = 10;
endx = 2;
decrement = -1; 

y = zeros(1,12);
for i = starty:endy
    y(i+1) = y(i) + ((5 - (4/50)*y(i)));
end
y
x = zeros(1,10);
for i = startx:decrement:endx
    x(i-1) = x(i) + ((5 + (4/50)*x(i)));
end
x

[Dennis M]

Thanks, but want a variable of start and end. For example : 17 to 30 or 20 to 45; 15 to 2 or 60 to 40 with decrementing step.

[Awais Saeed]

I am having difficulty in trying to understand your question. Do you want your first loop to start from 17 or 20 and end at 30 or 45? If that is the case just do

starty = 17;
endy = 30;

Same goes for the second loop. 'starty' and 'endy' are variables.

[Dennis M]

<<

>> There was error when I change the variables, I have to change also the y = zeros(1,12); defend on the length. I want a loop that the output is like this (10 20 29 38 47 56 65 and so on) and (80 70 61 53 46 40 35 and so on) same in negative (-10 -20 -29 -38 -47 -56 -65 and so on) and (-80 -70 -61 -53 -46 -40 -35 and so on)