Plot an equation in time span T=[0,t]

Hi,

I am about to plot an equation but i have 4 variables (including t), how can I plot this equation in domain of 0-T ?

clc
clear
close all

a=input('Please enter a : ')
b=input('Please enter b : ')
c=input('Please enter c : ')
t=input('Please enter t : ')


if(a*b/c>1)
    for(0:t)
    y=(e^a)*sin(c*t)/sqrt(b);
    plot(t,y)
    end 

elseif(a*b/c<1 && a*b/c>0)
        y=sin(a)*sqrt(b*t)/sin(c);
        plot(t,y)

elseif(a*b/c<1)
        y=cos(a)*e^(b*t)/(c);
        plot(t,y)
        end

thanks

Answer 1

[Karim]

You need to create a vector, below you can see a method using the "linspace" function. This creates a vector between 0 and t with 100 elements.

a = 3; % input('Please enter a : ')
b = 2; % input('Please enter b : ')
c = 7; % input('Please enter c : ')
t = 5; % input('Please enter t : ')

% create a vector T between [0 T] with 100 elements
t = linspace(0,t,100);

check = a*b/c;

if check > 1
    y = (e^a)*sin(c.*t)./sqrt(b);
elseif check <= 1 && check >= 0
    y = sin(a)*sqrt(b.*t)./sin(c);     
else % i.e. check < 1
    y = cos(a)*e.^(b.*t)./c;    
end

figure
plot(t,y)
xlabel('t axis')
ylabel('y values') 
grid on

[Torsten]

You mean

if (a*b/c>1)
    y = (e^a)*sin(c.*t)./sqrt(b);
elseif (a*b/c<=1 && a*b/c>=0)
    y = sin(a)*sqrt(b.*t)./sin(c);    
elseif (a*b/c<0)
    y = cos(a)*e.^(b.*t)./c;
end

instead of

if (a*b/c>1)
    y = (e^a)*sin(c.*t)./sqrt(b);
elseif (a*b/c<1 && a*b/c>0)
    y = sin(a)*sqrt(b.*t)./sin(c);    
elseif (a*b/c<1)
    y = cos(a)*e.^(b.*t)./c;
end

don't you ?

[Fatemeh Salar]

@Torsten

Yes, I've also forgot to put "." notion since its element-wise operations! Thanks

Answer 2

[Fatemeh Salar]

Dear @Karim

Thank you so much.