Problem with hold onand plotyy

I am tying to use a plotyy and hold on to plot 4 diagrams in 2 y axes and it did not work, can anybody see where is the problem? it only plot 2 first diagrams

load dexpan2Cp;
x1=dexpan2Cp(:,2);
x1=x1/3600;
y1=((dexpan2Cp(:,3)+dexpan2Cp(:,4))/2000)*32.5;

load Dexpan2_2C;
x2=Dexpan2_2C(:,1);
x2=x2/3600;
y2=Dexpan2_2C(:,2);

A = importdata('Scan Session94-Dexpan19.txt','\t',5); 
Dexpan19p=A.data;
save('Dexpan19p.mat','Dexpan19p');

x3=Dexpan19p(:,2);
x3=x3/3600;
y3=((Dexpan19p(:,3)+Dexpan19p(:,4))/2000)*32.5;

load Dexpan19C;
x4=Dexpan19C(:,1);
x4=x4/3600;
y4=Dexpan19C(:,2)+3.3;

x1 = x1(x1<115.7); y1 = y1(1: length(x1) , :);
x2 = x2(x2<115.7); y2 = y2(1: length(x2), :);
x3 = x3(x3<115.7); y3 = y3(1: length(x3), :);
x4 = x4(x4<115.7); y4 = y4(1: length(x4), :);

hold off;
figure;
[ax, h1, h2] = plotyy(x1,y1,x2,y2);
set(h1,'g',y1,'DisplayName','1');
set(h2,'b',y2,'DisplayName','2e');
hold(ax(1),'on');

plot(ax(1),x3,y3,'r',y3,'DisplayName','3');
hold(ax(2),'on');
plot(ax(2),x4,y4,'k',y4,'DisplayName','4');

xlabel('Time (h)');
ylabel(ax(1),' Pressure (MPa)');
ylabel(ax(2),'Tempereture (°C)');
legend('show');

result

Answer 1

[dpb]

set(h1,'g',y1,'DisplayName','1');

is a syntax error, the handle object returned in h1 from plotyy is (possibly an array of) line handle(s) to the lines on the LH axes (and similarly for RH axes in second). The set command syntax to set the color for the line associated with h1 would be

set(h1,'color','g','DisplayName','1');

as it has no way to associate the variable with the handle and the property name is 'color', not a list of default colors as would be required for the above to work.

plot(ax(1),x3,y3,'r',y3,'DisplayName','3');

Similarly, there's a syntax in the follow-on plot command above; the triplet form is plot(x,y,linespec,...); again there's no connection to the variable excepting by position. Use

plot(ax(1),x3,y3,'r','DisplayName','3');

instead. It would be good practice to return a line handle to these additional lines by augmenting the two handle variables into arrays so you have access to them directly for further manipulation if needed, but not mandatory. Also, if the lengths of the timeseries are the same you can place the y-values to go on each axes in an array by column and plot in one call to plotyy() instead of multiple...

[hAx,hL1,hL2]=plotyy([x1 x3],[y1 y3],[x2 x4],[y2 y4]);

where the arrays are assumed to be the same length and column vectors, fixup as necessary if not but just showing possible alternate and perhaps simpler syntax...

[Atteyeh Natanzi]

Thank you but it did not work

[dpb]

What does "did not work" mean, precisely? Show your work; some sample data would help; can't reproduce your efforts here but certainly I can generate two lines on the two axes at will...

[Atteyeh Natanzi]

I did the changes and can not run it. Here is my data. I would really appreciate if you could help.

[dpb]

Your .mat files don't match up with the script...some have x,y vectors, some still have the Dex*** variables. You need to go back to the beginning and work through with a consistent set of data first, then make the changes I noted earlier in the syntax of the plot commands.

>> whos -file dexpan19c
Name                 Size               Bytes  Class     Attributes
Dexpan19C      1371168x2             21938688  double              
>> whos -file dexpan19p
Name           Size              Bytes  Class     Attributes
x3        500000x1             4000000  double              
y3        500000x1             4000000  double              
>> whos -file dexpan2_2C
Name                 Size              Bytes  Class     Attributes
Dexpan2_2C      416695x2             6667120  double              
>> whos -file dexpan2Cp
Name           Size              Bytes  Class     Attributes
x1        500000x1             4000000  double              
y1        500000x1             4000000  double              
>>

Not knowing then who's been scaled and how, difficult to make realistic plot. But, the script won't run when try to use the wrong variable name after load for the files that aren't consistent first, then the issue of scaling or not having been done consistently, etc., ...