How to plot only few points in X axis and y axis

I have certain points only to be plotted on x axis from over all length of the beam.

My beam length is 1 metres and i want to plot slope and deflection at only few points like 0.333, 0.666, etc distance of the beam. How can i do that . currently i am using below code to plot everything over the lenght. but i want to see only thos points listed.

x1=linspace(0,1,N);
x2=linspace(0,1,N);
figure
subplot(1,2,1)
plot (x1,d)
title('Length vs Displacement')
xlabel('Length')
ylabel('Displacement')

subplot(1,2,2)
plot (x2,s,'r-x')
title('Length vs Slope')
xlabel('Length')
ylabel('Slope')

Answer 1

[Ameer Hamza]

Try this.

x=linspace(0,1,N);
xq = 0.333:0.333:1;

dNew = interp1(x, d, xq);
sNew = interp1(x, s, xq);

figure 
subplot(1,2,1) 
plot (xq, dNew) 
title('Length vs Displacement') 
xlabel('Length') 
ylabel('Displacement')

subplot(1,2,2) 
plot (xq, sNew,'r-x') 
title('Length vs Slope') 
xlabel('Length')
ylabel('Slope')

[shekar gundavarapu]

Hi, Thanks for the comments. it is giving out error saying that N is undefined variable. Undefined function or variable 'N'.

Error in simplysupportedcase_1_27ele (line 171) x1=linspace(0,1,N);

in my case i need to plot 2 graphs..length vs slope ans length vs deflection. so added below lines and it's failing. also in my code i have added N as one parameter or input. see attached

[Walter Roberson]

In your code N should probably be N1 or N2

[shekar gundavarapu]

It did not work and i got below error.

Error using interp1>reshapeAndSortXandV (line 424) X and V must be of the same length.

Error in interp1 (line 93) [X,V,orig_size_v] = reshapeAndSortXandV(varargin{1},varargin{2});

Error in simplysupportedcase_1_27ele (line 176) dNew = interp1(x1, d, xq)

Ps.: I am very new to matlab

[Walter Roberson]

x = linspace(0, 1, length(d));

[Ameer Hamza]

@shekar, since the code in your question already included N so I assumed that you already know what it is. Your question also shows that d and s have the same length. If it not the case, you can modify the code as follow

x1=linspace(0,1,length(d));
x2=linspace(0,1,length(s));
xq = 0.333:0.333:1;
dNew = interp1(x1, d, xq);
sNew = interp1(x2, s, xq);

figure 
subplot(1,2,1) 
plot (xq, dNew) 
title('Length vs Displacement') 
xlabel('Length') 
ylabel('Displacement')
subplot(1,2,2) 
plot (xq, sNew,'r-x') 
title('Length vs Slope') 
xlabel('Length')
ylabel('Slope')

[shekar gundavarapu]

Thank you..Will try and let you know