Polarity different dimension summation

I have bipolar signal as positive and negative as shown in the following

x=[-1 8 2 -3 -5  6 -4 5 -8 7 -9 4 5 -10 -6 -11 8 3 7 1 -5 -20 14 18 19 -16 8 16 -17 -15];
Xp=x(x>0);
Xn=x(x<0);
figure(1)
stem(Xn);
title('negative signal');
Xn=abs(Xn);
figure(2)
stem(x);
title('orginal signal');
figure(3)
stem(Xp);
title('positive signal');
figure(4)
stem(Xn);
title('abs negative signal'); 

I want to send the two parts (positive and negative) by combining the two parts in a sequential way.

[madhan ravi]

Give an example of your desired output.

Answer 1

[Walter Roberson]

Like I told you before, https://www.mathworks.com/matlabcentral/answers/439423-sum-first-matrix-and-second-matrix#comment_659789

You can concatenate them if you have reason to,

[Xn, Xp]

but you would need to keep track of the size of at least one of the two if you need to separate them out again.

[abdullah qasim]

I want to put a break between the first and second parts as follows

Xn+S

[Walter Roberson]

What should the break be filled with? MATLAB does not permit you to have numeric matrices with "gaps" in them.