problem using stem command

Hi,

I want to plot some point by using stem comand but I recieve error. can any body guide me. point are lev_press and I need to mark them in between rec_start and rec_stop.

error:

Subscript indices must either be real positive integers or logicals.

Error in example (line 87)

stem(x,lev_press(1,r),':diamondr')

data

rec_start = 1.625608000000000e+03;

rec_stop=1.655613000000000e+03;

x = rec_start:1:rec_stop;

lev_press=[1629.599, 1630.297, 1633.178];

for r = lev_press 1:1:3

figure

stem(x,lev_press(1,r),':diamondr')

end

Answer 1

[Star Strider]

Try this:

rec_start = 1.625608000000000e+03;
rec_stop=1.655613000000000e+03;
lev_press=[1629.599, 1630.297, 1633.178];
x = linspace(rec_start, rec_stop, numel(lev_press));

figure
stem(x, lev_press)
grid
ylim([1600 1650])                                       % Optional (‘Zooms’ Plot)

The ylim call makes the slight variation in the ‘lev_press’ values more visible.

[Muhammad Haziq]

Thanks to both for the reply. I ploted the fig but have some error like it is not ploting correct point. like point should be on 1629, 1630, 1633 instead of that

1625, 1640and 1655 what should I do?

I want to plot lev_press values between the x range.

[Star Strider]

Try this:

lev_press=[1629.599, 1630.297, 1633.178];
x = floor(linspace(rec_start, rec_stop, numel(lev_press)));

figure
stem(x, lev_press)
grid
xlim([1620 1660])
ylim([1600 1650])                                       % Optional (‘Zooms’ Plot)

[Star Strider]

Muhammad Haziq’s Answer moved here:

It gives the same result, well actually I need to plot some point with respecto to x axis(let say it is time) only, I don't care about the y. so that I can mark rec_start, then I can mark lev_press point and finally I mark rec_stop point.

so can any one guide how to do it

[Star Strider]

Please be more specific.

How are ‘rec_start’, ‘rec_stop’, and ‘lev_press’ related? Are they themselves times, or something else?

I have no idea what your data represent, or what you want to do.

I am guessing. Try this:

rec_start = 1.625608000000000e+03;
rec_stop=1.655613000000000e+03;
lev_press=[1629.599, 1630.297, 1633.178];
x = linspace(rec_start, rec_stop, numel(lev_press));

figure
stem(lev_press, ones(size(lev_press)), 'filled')
grid
xlim([rec_start rec_stop])
text(rec_start, 0.05, sprintf('\\bf\\leftarrowStart'), 'HorizontalAlignment','left')
text(rec_stop, 0.05, sprintf('\\bfStop\\rightarrow'), 'HorizontalAlignment','right')

See if that does what you want.

[Muhammad Haziq]

Hi,

Thanks for the reply and helping me, this resolve my problem.

Regards,

Haziq

[Star Strider]

As always, my pleasure.