Which is the easiest method for shifting binary digits to the right?

Question

Darsana P M 2018-2-15

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/382777-which-is-the-easiest-method-for-shifting-binary-digits-to-the-right

评论： Walter Roberson 2018-2-23

x1 = {'1' '0' '1' '1' '0' '1' '0' '0' '0' '1' '1' '1' '0' '0' '1' '1'};
x=hex2dec(x1);

Thus in command window,

Hence to do shift operation, which is the simplest way?

by one place, 0110100011100110

next, 1101000111001100

next , 1010001110011000

and so on?

Can somebody help me?

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Walter Roberson 2018-2-15

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/382777-which-is-the-easiest-method-for-shifting-binary-digits-to-the-right#answer_305233

在 MATLAB Online 中打开

[x(2:end), 0]

4 个评论
显示 2更早的评论隐藏 2更早的评论

Walter Roberson 2018-2-18

在 MATLAB Online 中打开

>> x = [     1
     0
     1
     1
     0
     1
     0
     0
     0
     1
     1
     1
     0
     0
     1
     1]
x =
     1
     0
     1
     1
     0
     1
     0
     0
     0
     1
     1
     1
     0
     0
     1
     1
>> [reshape(x(2:end), 1, []), zeros(1, min(1, length(x)))].'
[reshape(x(2:end), 1, []), zeros(1, min(1, length(x)))].'
ans =
     0
     1
     1
     0
     1
     0
     0
     0
     1
     1
     1
     0
     0
     1
     1
     0
>> length(ans)
ans =
    16

Or you could be lazy in your error checking and just use

[x(2:end); 0]

Darsana P M 2018-2-23

thanks for the answer sir.

请先登录，再进行评论。

Answer 2

Darsana P M 2018-2-23

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/382777-which-is-the-easiest-method-for-shifting-binary-digits-to-the-right#answer_306652

在 MATLAB Online 中打开

for i=1:1:16
     if x(i) == 0
        % yj = y;
        Z = Z
     else x(i) == 1
        Z = bitxor(Z,v);
     end    
        if lsb == 0
           v = [v(i:end); 0];
        else lsb == 1
            v = [v(i:end); 0];
            v = bitxor(v,R);
       end    
   end

I got an error stating this: Error using bitxor Inputs must have the same size.

Error in shifty (line 38) Z = bitxor(Z,v);

When I checked the size of v it was, 17

4 个评论
显示 2更早的评论隐藏 2更早的评论

Darsana P M 2018-2-23

So, what correction should i do??

Walter Roberson 2018-2-23

在 MATLAB Online 中打开

You can get around the first problem by changing

v = [v(i:end); 0]

to

v = [v(i+1:end); 0]

However, this will just postpone the problem one iteration: on the next iteration you will be generating a shorter v (because i has increased) and that shorter v will fail the Z = bitxor(Z,v) since Z did not also get shorter.

I think you need to revise your algorithm. One of the major revisions you need is that you need to document the code -- the purpose of the code, and a description of what you expect each step to accomplish.

请先登录，再进行评论。