Undefined function or method 'E' for input arguments of type 'double'. And how to do summation of functions

I want to perform the following task on MATLAB: d(m)=d0(m)+∑_(n=1)^48▒〖Eo(m,n).(do(i).[p(n)-p0+A]/p0)〗 where d0, p0, A are known and p(n) and Eo(m,n) value depend on some conditions. Here is my code:

p0=25.44;
A=p0;
m=1:48;
i=m/2;
n=1:48;
j=n/2;

d0(m)=[0.798,0.742,0.82,0.819,0.962,0.854,0.792,0.825,0.782,0.783,0.722,0.775,0.954,0.736,0.807,0.926,1.18,0.917,1.37,3.279,1.453,2.02,1.245,1.518,2.561,2.048,1.208,2.066,1.756,1.486,0.987,1.192,1.46,1.313,0.936,0.931,1.004,0.901,1.202,1.863,4.04,2.268,1.095,0.983,1.79,1.378,0.907,0.857];

if(i>=0&i<=9&j>=0&j<=9)|(i>9&i<=19&j>9&j<=19)|(i>19&i<=24&j>19&j<=24)
E(m,n)=-0.1;
elseif (i>=0&i<=9&j>19&j<=24)|(i>19&i<=24&j>=0&j<=9)
E(m,n)=0.012
elseif (i>=0&i<=9&j>9&j<=19)|(i>9&i<=19&j>=0&j<=9)
E(m,n)=0.01;
elseif (i>9&i<=19&j>19&j<=24)|(i>19&i<=24&j>9&j<=19)
E (m,n)=0.016;
end

if(i>=0&i<=9)
p(n)=15;
elseif i>9&i<=19
p(n)=25;
else
p(n)=30;
end
for n=1:48
B=(E(m,n).*(d0(m)*(p(n)-p+A)/p0));
S=sum(B(:));
end
d(m)=sum+d0(m);
plot(i, d0(m),i, d(m));
axis([0.5 24 0 5])
d(m)

It keeps showing the error: Undefined function or method 'E' for input arguments of type 'double'.

What do I do to rectify it?

I want to basically find the values of d(m) for each value of d0(m) using the above equation. Do you have another code for it?

Answer 1

[David Young]

The value of i is the vector (1:48)/2. That means that the four tests on the value of i don't make sense - they all return false, and so E is never given a value.

It looks like you might mean to put these tests inside a loop, so that i and j have scalar values. Then you probably need to set E(i,j) to a value rather than E(m,n). Can you try writing some much simpler code to solve a similar problem, so that you understand how it works, before trying to write the code for this problem?