# How do I plot lines with different line widths?

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Leor Greenberger on 22 Sep 2011
Answered: SHAILENDRA PANDEY on 11 Oct 2020
Hi,
I want to do:
plot(x1,y1,x2,y2,'LineWidth',8)
but the linewidth propery ends up applying to both lines. Do I have to use two plot functions with a hold on command to have line1 a different width than line2? Thanks.
##### 2 CommentsShowHide 1 older comment
Ramesh M on 28 Jul 2016
it works thnx

Fangjun Jiang on 22 Sep 2011
Edited: MathWorks Support Team on 8 Nov 2018
To plot two lines with different line widths, you can use either of these approaches.
1. Return the two “Line” objects as an output argument from the “plot” function and then set the “LineWidth” property for each.
p = plot(x1,y1,x2,y2)
p(1).LineWidth = 5;
p(2).LineWidth = 10;
2. Use the “hold on” command to plot the two lines separately. Specify the line width by setting the “LineWidth” property a name-value pair.
plot(x1,y1,'LineWidth',5)
hold on
plot(x2,y2,'LineWidth',10)
hold off
##### 2 CommentsShowHide 1 older comment
Mike Garrity on 8 Mar 2016
Just FYI, there is an "official" syntax for setting a property to different values on different objects. However, it's really ugly, and doesn't work everywhere. For example, I don't think that the plot function accepts this form.
It looks like this:
h = plot(x1,y1,x2,y2);
set(h,{'LineWidth'},{5;10})
The property name and property value need to each be a cell array, and the shape of the value cell array has to match the shape of the handle cell array.
That said, you're really better off with 2 calls to set in this case.

Wayne King on 22 Sep 2011
Hi: You can use handles.
h = plot(x1,y1,x2,y2);
set(h(1),'linewidth',1);
set(h(2),'linewidth',2);

Hari Desanur on 15 Nov 2016
Edited: Hari Desanur on 15 Nov 2016
The line width for a particular line can be set using line object handles. For example -
l = plot(x1,y1,x2,y2);
l(1).LineWidth = 3; % set line width of 3 for the first line (x1,y1)
l(2).LineWidth = 6;

MASTER WHOS on 14 Feb 2019
1-What might be the problem? 2-What does linewidth property mean? 3-What to do?
[I am using matlab R2016b]
When I want to plot line with color and certain width, I recceive an error:
THE COMMAND
plot(SNR_db,Pd_NSP_cat_mean(:,2),'b','LineWidth',2.5)
THE ERROR:
Error using plot
There is no LineWidth property on the Line class.
Error in PROJECTION_BASED_SHARING (line 76)
plot(SNR_db ,Pd_NSP_cat_mean(:,1),'g','LineWidth ',2.5)

SHAILENDRA PANDEY on 11 Oct 2020
x = 1:.01:10;
y1 = sin(x);
y2 = cos(x);
p = plot(x,y1,x,y2)
set(p,{'LineWidth'},{5;10})
Line width, specified as a positive value in points, where 1 point = 1/72 of an inch. If the line has markers, then the line width also affects the marker edges.
The line width cannot be thinner than the width of a pixel. If you set the line width to a value that is less than the width of a pixel on your system, the line displays as one pixel wide.