Defining the limits for discrete time sequence on x axis using stem command

In this sample program, I need to define the x axis as integers only rather than fractions.

x=[-2 1 -1 2]

nx=-1:2

h=[0 1 2]

nh=0:2

subplot(311)

stem(nx,x,'k')

xlabel('n')

ylabel('x(n)')

title('Input sequence x(n)')

subplot(312)

stem(nh,h,'k')

xlabel('n')

ylabel('h(n)')

title('Impulse Response h(n)')

[Daniel M]

What is the question

[altaf ahmed]

Question: in the plots, the horizontal axis are needed to be integers only. Somehow they are coming in fractions. Is there a way to define this in stem command or plot command.

Answer 1

[Star Strider]

Add these lines to each subplot:

xt = get(gca, 'XTick');
set(gca, 'XTick',min(xt):max(xt))

so the revised code is now:

x=[-2 1 -1 2]
nx=-1:2
h=[0 1 2]
nh=0:2
subplot(311)
stem(nx,x,'k')
xt = get(gca, 'XTick');
set(gca, 'XTick',min(xt):max(xt))
xlabel('n')
ylabel('x(n)')
title('Input sequence x(n)')
subplot(312)
stem(nh,h,'k')
xt = get(gca, 'XTick');
set(gca, 'XTick',min(xt):max(xt))
xlabel('n')
ylabel('h(n)')
title('Impulse Response h(n)')

Note that here, the minimum and maximum x-tick values are integers. If they are not in other plots, you will have to change the added lines appropriately to make them integer values, for example:

set(gca, 'XTick',floor(min(xt)):ceil(max(xt)))

Experiment to get the result you want.