# Plotting for a wide range of values and Log-Log Scale

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Burcu Yilmaz on 2 Jan 2020
Answered: Roshni Garnayak on 10 Jan 2020
Hello!
Here is my code,
for dt = 1:10
x=5;
x_arr=[];
x_arr(1)=x;
for i=1:10/dt
xnew=x*dt;
x=xnew;
x_arr(i+1)=xnew;
end
Difference=abs(x_arr(1)-x_arr(end))
hold on
plot(dt,Difference,'o')
end
hold off
ylabel('Difference between initial and final x value')
xlabel('dt')
I want to run this code for small dt values dt=10^-6:10^0
I know that in order to get a reasonable plot I should use loglog scale. However, I couldn't do that. Can you help me to understand how to use loglog scale for my code.

Roshni Garnayak on 10 Jan 2020
If you attempt to plot the data using ‘loglog’ with ‘hold on’ enabled, the data plots as a linear plot. You can store the ‘Difference’ and ‘dt’ values in arrays and plot the data outside the for loop. The code can be modified in the following way:
Difference = [];
DT = [];
for dt = 1:10
x=5;
x_arr=[];
x_arr(1)=x;
for i=1:10/dt
xnew=x*dt;
x=xnew;
x_arr(i+1)=xnew;
end
Difference = [Difference, abs(x_arr(1)-x_arr(end))];
DT = [DT, dt];
end
loglog(DT, Difference, '-o');