I wrote a code for determining the volume need for each stage of a rocket

clear;clc
%create the statement

radius1=16.5;height1=138.0;radius2=16.5;height2=81.5;radius=30.8;height3=61.6;

height=input('Enter a value for height');
volume=(height)
if height<=138
   volume=(pi*height*radius1^2)
   disp(volume)
elseif height<=219.5
    volume=(pi*height1*radius1^2+pi*(138-height)*radius2^2)
    disp(volume)
elseif height<=281.1
   volume=(pi*height1*radius1^2+pi*(138-height)*radius2^2+pi*(219.5-height)*radius3^2)
   disp(volume)
else height>281.1
    disp(-1)
end

I run it through the checker and the code is still wrong when I run it through the grader. What might I be doing wrong in writing my code. I gave the height and radius in each stage above and I am using the volume formula for a cylinder.

[dpb]

What should the net height be of higher stages????

Answer 1

[Youssef Khmou]

Steven, The error i can see is that the volume is negative, because you substract the height from 138 & 219.5 while its the reverse, try this version :

clear;
radius1=16.5; height1=138.0;
radius2=16.5; height2=81.5;
radius3=30.8; height3=61.6;
height=input('Enter a value for height:\n');
if height<=138
 volume=(pi*height*radius1^2);
elseif (height>138) && (height<=219.5)
  volume=(pi*height1*radius1^2+pi*(height-138.00)*radius2^2);
elseif (height>219.5)&&(height<=281.1)
 volume=(pi*height1*radius1^2) + (pi*(height-138.00)*radius2^2) + ...
     (pi*(height-219.5)*radius3^2);
elseif height>281.1
  error(' Maximum height exceeded hmax=281.1');
end
fprintf(' Volume=%.2f m^3\n',volume);

[dpb]

I'd preferred the hint version for HW problems instead of just doing it for the poster...but that's me.