Help debugging a code? Says function makes an error but when I run it, it returns the correct output...

2017 8 20
1 个回答
更新时间：2017 8 20
3 次查看（30 天）

0 个投票

I'm having trouble with the following assignment:
Write a function called sort3 that takes a 3-element vector as its sole arguments. It uses if-statements, possibly nested, to return the three elements of the vector as three scalar output arguments in non- decreasing order, i.e., the first output argument equals the smallest element of the input vector and the last output argument equals the largest element. NOTE: Your function may not use any built-in functions, e.g., sort, min, max, median, etc.
Here is what I've done so far:
function [a,b,c]=sort3(A)
a= A(1); b=A(2); c=A(3);
if (a<=b)&& (b<=c)
if a<b && b<c
output= [a b c]
elseif(a==b)&& b<c
output= [a b c]
elseif a<b && (b==c)
output= [a b c]
else a==b==c
output= [a b c]
end
elseif (a<= c)&& (c<=b)
if (a<c)&& (c<b)
output= [a c b]
elseif (a==c)&& a<b
output= [a c b]
elseif a<c && (c==b)
output= [a c b]
else a==c==b
output= [a c b]
output = [a c b]
end
elseif (b<=c) && (c<=a)
if b<c && c<a
output= [b c a]
elseif (b==c)&& c<a
output= [b c a]
elseif b<c &&(c==a)
output= [b c a]
else b==c==a
output= [b c a]
end
elseif (b<=a) && (a<=c)
if b<a && a<c
output= [b a c]
elseif (b==a)&& b<c
output= [b a c]
elseif b<c &&(c==a)
output= [b a c]
else b==c==a
output= [b a c]
end
elseif (c<=a) && (a<=b)
if c<a && a<b
output= [c a b]
elseif (c==a)&& a<b
output= [c a b]
elseif c<a && (a==b)
output= [c a b]
else c==a==b
output= [b c a]
end
else (c<=b) && (b<=a)
if c<b && b<a
output= [c b a]
elseif (c==b)&& b<a
output= [c b a]
elseif c<b && (b==a)
output= [c b a]
else b==c==a
output= [b c a]
end
end
I ran it through an autograder and it said:
Feedback: Your function performed correctly for argument(s) [1 2 3]
Feedback: Your function made an error for argument(s) [1 3 2]
But when I set A= [1 3 2], it seems to return the output [1 2 3].
Also -- I totally realize that my code is very inefficient. What are some ways I could make my code more efficient?
Thank you!

请先登录，再回答此问题。

回答（1 个）

per isakson
per isakson 2017-8-20
编辑：per isakson 2017-8-20

0 个投票

IMO: Your code is a nightmare to debug and I will not try.
There is a problem with output. It's not used as output.
Proposal: See varargout, Variable-length output argument list and replace
function [a,b,c]=sort3(A)
by
function varargout = sort3(A)
and all the
output = [ ...]
by
varargout = { ... }; % e.g.
varargout = { b, c, a };
If that doesn't help see Bubble sort
In response to comment:
Add this line at the end of your code
a = out(1); b = out(2); c = out(3);
Replace
else b==c==a
by
elseif b==c && c==a
or whatever it's intended to be

类别

在 帮助中心 和 File Exchange 中查找有关 Shifting and Sorting Matrices 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by