How do I read these arrays into the function to input more than just one answer?

a=500

alpha=[54.80,54.06,53.34]

beta=[65.59,64.59,63.62]

x=a*(tan(beta)/(tan(beta)-tan(alpha)))

It only outputs the last answer with the last set of angles and I need it at all three angles.

Answer 1

[John BG]

Sean

a start point could be

 function x=f1(a,alpha,beta)

    x=a*(tand(beta)./(tand(beta)-tand(alpha)))

 end

call example

a=500
alpha=[54.80,54.06,53.34]
beta=[65.59,64.59,63.62]
x=f1(a,alpha,beta)

tan is for rad angles, tand for degree angles.

any function, to be robust, has to be able to block non coherent inputs, like chars instead of numbers, or alpha and beta with different lengths, or if you only want it to work on reals, then remove the imaginary parts.

many functions also usually include a few comment lines right below the function header, that show up when keying in 'help function_name' in MATLAB Command Window.

there are commands like

nargin 
nargout 
arginchk 
argoutchk 
varargin 
varagout

to help building input output checks

the function, including a few input checks would be

function [x,err_code]x=f1(a,alpha,beta)

     arginchk(3,3);  % only 3 inputs
     argoutchk(1,1)  % only 1 output

     err_list={'err message 1';'err_message 2'}
     err_code=0;  
     if numel(a)>1
       err_code=1;
       disp('err_list{1}')
       break; 
     end

     % stretch angles to avoid possible size mismatch
     alpha=alpha(:);beta=beta(:); 

     if numel(alpha)!=numel(beta)
        err_code=2;
        disp(err_code_list{err_code})
        break; 
     end

     x=a*(tand(beta)./(tand(beta)-tand(alpha)))

   end

if you find this answer useful would you please be so kind to mark my answer as Accepted Answer?

To any other reader, please if you find this answer of any help solving your question,

please click on the thumbs-up vote link,

thanks in advance

John BG

<mailto:[e-mail] [e-mail]>

[John BG]

Perhaps you may want to consider the alternative expression to

    x=tand(beta)./(tand(beta)-tand(alpha))

being

x=1-.5*sind(alpha+beta)./sin(alpha-beta)

because tangent gets to Inf and -Inf periodically, MATLAB may throw less warnings for possible inaccurate calculations due to too close to Inf

Answer 2

[Image Analyst]

You used slash for divide, when you should have used dot slash

x = a*(tan(beta) ./ (tan(beta)-tan(alpha)))

to do an element-by-element divide for every element in the arrays.