MATLAB: Simple problem using for loop/array

arrayforloopsmatrixmultiplication

Hello, I am quite new to Matlab and have read through Help sections, forums etc, but I still cannot get my basic code to correctly execute multiplying a constant by array (I have tried matrix too) and give me the answer that is correct.
clear all; clc
A=0.4; %  bond albedo
AU=1.496*10^11 
row=5.67*10^-8;  % boltz const
L=3.84*10^26;    % lum sun
num1=(1-A)*L;
% calc denominator
den=16*pi*row;
temp_range=[373.15; 273.15]  %matrix 2x1
% temp_range=[373.15 273.15] %array
k=den.*((temp_range).^4)
% calc habitable zone
distance=(num1/k).^0.5
hab=distance/AU
 % second attempt
 % 
% for i=temp_range;
%     k=den.*(i.^4)
% end    
% d=(num1/k).^0.5
% hab=d/AU
% disp(hab)
    % code
  end
The output of this gives me answers to one of the temperature range only, either 0.4 or 0.8, with the other value in the array Or matrix (tested both) being zero. eg.Output gives ;
    % hab =
    0.4316         0
and the same result but with a 2×1 matrix, that second value should be 0.8xxx etc. The second attempt yields exactly the same result.
What steps have I done wrong/missed completely? (I have not provided the entire code, just a snippet for the problem seen, if required I will provide the constants missing/entire code)
Kind regards,
Jay

Best Answer

Hi,
Please use this. It gives the output as you have requested above.
    clc;
    A=0.4; %  bond albedo
    AU=1.496*10^11; 
    row=5.67*10^-8;  % boltz const
    L=3.84*10^26;    % lum sun
    num1=(1-A)*L;
    % calc denominator
    den=16*pi*row;
    temp_range=[373.15; 273.15];  %matrix 2x1
    % temp_range=[373.15 273.15] %array
    k=den.*((temp_range).^4);
    % calc habitable zone
    for i = 1:length(k)
    distance(i)=(num1/k(i)).^0.5;
    end;
    hab=distance/AU;
Thanks.
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