Dont see why this code doesnt work

for i=1:11 
x = z(i)/0.9;  
pipeLength = sqrt(x.^2+z.^2); 
if pipeLength <= 10 
pipeCost(i) = price1*pipeLength
else 
pipeCost(i) = price1*10 + price2*(pipeLength-10); % Price for lengths greater than 10 m 
end 
end

My program works fine up until this point.

I am trying to compute the cost of pipe depending on the length. Lengths up to 10 feet are 25 while anything after is 15. When I run the program it gives me the error,

In an assignment  A(I) = B, the number of elements in B and I must
be the same.

Error in waterpipe (line 34)
pipeCost(i) = price1*10 + price2*((pipeLength)-10); % Price for
lengths greater than 10 m

any ideas?

Answer 1

[Azzi Abdelmalek]

Use pipeCost(i,:) instead of pipeCost(i)

z=rand(1,11)
price1=1;
price2=2
for i=1:11
  x = z(i)/0.9;
  pipeLength = sqrt(x.^2+z.^2);
  if pipeLength <= 10
      pipeCost(i,:) = price1*pipeLength
  else
      pipeCost(i,:) = price1*10 + price2*(pipeLength-10); 
  end
end

Answer 2

[Image Analyst]

When you say this

pipeLength = sqrt(x.^2+z.^2);

x is a scalar (single number), but z is an array. So pipeLength is an array of several numbers. Which means price1*10 + price2*(pipeLength-10) is also an array of several numbers. However you are trying to stick that array into a single element of pipeCost. Can't do that. It can be a whole row of pipeCost if you make pipeCost a 2D array, or make pipeLength a scalar:

pipeLength = sqrt(x.^2+z(i).^2);

Answer 3

[Jason]

With the way I have the code written, what is it that MATLAB doesnt like? All I can think of is that it doesnt want me to be subtracting from pipeLength in the way I have it.

[Image Analyst]

No. Did you not read my detailed explanation? Again, it doesn't like you stuffing a bunch of numbers into an array element that can take only a single number.

[Azzi Abdelmalek]

Jason, Edit your question or add a comment to any answer of your choice by clicking on comment on this answer