Need help flipping elements in an array without using built in functions

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Yousef 2014-11-6

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https://ww2.mathworks.cn/matlabcentral/answers/161510-need-help-flipping-elements-in-an-array-without-using-built-in-functions

编辑： per isakson 2014-11-11

Here is the problem i am trying to work with:

Develop a user-de

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Image Analyst 2014-11-6

http://www.mathworks.com/matlabcentral/answers/38787-what-can-be-programmed-without-any-built-in-functions

per isakson 2014-11-6

编辑：per isakson 2014-11-9

@Image Analyst, Given Walter's rules, isn't it impossible to write a bubble-sort routine? I assume that's the task. Is &nbsp + &nbsp to be regarded as syntactic sugar for the function &nbsp plus

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per isakson 2014-11-6

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https://ww2.mathworks.cn/matlabcentral/answers/161510-need-help-flipping-elements-in-an-array-without-using-built-in-functions#answer_157881

编辑：per isakson 2014-11-6

在 MATLAB Online 中打开

Hint:

    vec = 1:12;
    ix  = 6;
    vec = vec( [(1:ix-2),ix,ix-1,(ix+1:end)] )
    vec =
         1     2     3     4     6     5     7     8     9    10    11    12

The fifth and sixth elements are flipped.

&nbsp

I'm a big fan of the debugging tools of Matlab! Here are some links on debugging in Matlab

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per isakson 2014-11-9

编辑：per isakson 2014-11-9

Try the following steps

describe exactly what the algorithm shall do. ... given input ..., produce output. Ascending or descending?
describe in words how you envision that the algorithm shall work
use pseudo code to describe the algorithm
return to your Malab code
step through a couple of really simple examples

per isakson 2014-11-10

编辑：per isakson 2014-11-11

在 MATLAB Online 中打开

I run your code. There are obviously problems. Do the following:

Put breakpoints at the lines after the two last &nbsp disp( * )
Step through the code with the double green arrow,[Continue].

    >> list = randi( 12, [1,6] );
    >> list = reflip( list )
         9    10     4     9     8     2
        10     9     4     9     8     2
    18          reflip = [flip(end-k+1:-1:1), flip(end-k+2:end)];
         2     8     9     4     9    10
         8     2     9     4     9    10
         9     4     9     2     8    10
         4     9     9     2     8    10
         2     9     9     4     8    10
         9     2     9     4     8    10
         9     2     9     4     8    10
         2     9     9     4     8    10
         9     2     9     4     8    10
         2     9     9     4     8    10
         2     9     9     4     8    10
    list =
         2     9     9     4     8    10
    >>

where

    function vec = reflip( vec )
        %{
    list = randi( 12, [1,6] );
    list = reflip( list )
        %}
        maximum=0;
        disp( vec )
        for k=1:numel(vec)
            for ii=1:numel(vec)
                if maximum < vec(ii)
                    maximum = vec(ii);
                    max_index=ii;
                end
            end
            flip = [vec(max_index:-1:1), vec(max_index+1:end)];
    disp( flip )
            reflip = [flip(end-k+1:-1:1), flip(end-k+2:end)];
    disp( reflip )
            vec = reflip;
        end
    end