# Multiple values of x what will be code

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rajdeep singh on 11 Feb 2020
Commented: Star Strider on 11 Feb 2020
%it is just a example i want to know if there are multiple number of say x with other constant say a and b. Is it possible to plot graph between x and y. I am working with similar code that i wrote below but graph is not showing. Clc; Close all; Clear all; A=5; B=6; X=4,9,56,33 Y=(a+b)/x Plot (X,Y)

Star Strider on 11 Feb 2020
Try this:
A=5;
B=6;
X = [4,9,56,33];
Y=(A+B)./X;
figure
plot (X,Y)
Use element-wise operations (the (.) operator) in the division. See Array vs. Matrix Operations for an extended discussion.

rajdeep singh on 11 Feb 2020
Thank you sir, but it is working perfectly for scalar.
Here is the real code
A=31*10^6; B=7.625*10^-43; C=8.38*10^-34; D=700; f=[23.27,24.72,33.18,34.63,44.08,44.54,44.99] i= arrayfun(@(z) ((2B*z^3)/(A*(exp((B*z))-1))),f) plot (f,i)
I tried arrayfun but still not working.
rajdeep singh on 11 Feb 2020
I mean / instead of ./ Is also working perfectly. For single valued x.
Star Strider on 11 Feb 2020
The arrayfun call (essentially a slow for loop) is not necessary here. Vectorised MATLAB commands make explicit loops and other such operations unnecessary.
If I understand correctly what you want to do, this should work:
A=31E6;
B=7.625E-43;
C=8.38E-34;
D=700;
f=[23.27,24.72,33.18,34.63,44.08,44.54,44.99];
zfcn = @(z) (2*B*z.^3)./(A*exp(B*z)-1);
figure
plot(f, zfcn(f))
grid
This works for vector ‘f’. Again, note the use of element-wise operations in the exponentiation and division. You can assign the output of ‘zfcn(f)’ to an intermediate variable if you wish. I do not here, and simply use it as an argument to the plot function.

fred ssemwogerere on 11 Feb 2020
While your question may not be so clear, from my understanding, you are trying to find a vector,"Y" from a vector of "X" values. Try this:
A=5; B=6; X=[4,9,56,33];
% your vector "Y". From this you can proceed with your plot
Y=arrayfun(@(z) (A+B)/z, X);

rajdeep singh on 11 Feb 2020
clc; close all; clear all;
A=31*10^6; B=7.625*10^-43; C=8.38*10^-34; D=700; f=[23.27,24.72,33.18,34.63,44.08,44.54,44.99] i= arrayfun(@(z) ((2B*z^3)/(A*(exp((B*z))-1))),f) plot (f,i)
rajdeep singh on 11 Feb 2020
Not working