a program that moves over matlab and bounces back at a certain point

Since I don't have a Matlab running environment at hand, I will answer any issues that I can understand from reading the code.Please point out any mistakes.

 if(yi>=18)
yi = obj.yi_-1;
elseif(yi<=5)
yi = obj.yi_+1;
end

If you chew this part of the code, you can see that obj.yi_ is reduced by 1 if the value obj.yi_ is greater than or equal to 18, i is increased by 1 if the value obj.yi_ is less than or equal to 5, and does nothing else.

Therefore, as far as the code is concerned, there are the following problems:

• Nothing happens when
• 6<=obj.yi_<=17
• obj is not known how is defined, so there is no way to indicate the correct implementation
  • It stops at (1,18) ever since it reaches (1,18), so is there an implementation that moves up and down somewhere?
• The current direction of movement is not indicated.
  • There is no problem with the above two if there is an implementation somewhere that is not mentioned in this question.However, , which stops at (1,18) ever after reaching the subject, (1,18), is clearly due to the fact that the current direction of movement remains positive without bouncing back on the wall.

• It stops at (1,18) ever since it reaches (1,18), so is there an implementation that moves up and down somewhere?

• There is no problem with the above two if there is an implementation somewhere that is not mentioned in this question.However, , which stops at (1,18) ever after reaching the subject, (1,18), is clearly due to the fact that the current direction of movement remains positive without bouncing back on the wall.

You might want to introduce a variable called v that represents the speed and convert it backwards when it bounces back into the wall.In the future, you will be able to change the speed and specify the modulus of wall elasticity.

v=1;
xi = 1;
yi = obj.yi_;
if(yi>=18)
yi = obj.yi_-1;
v=-v;
elseif(yi<=5)
yi = obj.yi_+1;
v=-v;
end