How can I obtain the difference between two data stored in workspace?

1 次查看（过去 30 天）

saleh shlimet 2023-11-30

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/2054152-how-can-i-obtain-the-difference-between-two-data-stored-in-workspace

评论： Star Strider 2023-12-4

I experimentally tested a motor and the measured speed and the reference speed were stored in the workspace. My supervisor asked me to obtain the speed error (the difference between the reference and the measured speed). How can I obtain it from the data stored in the workspace?

5 个评论
显示 3更早的评论隐藏 3更早的评论

saleh shlimet 2023-12-3

thanks I tried hold on and it is working.

Star Strider 2023-12-3

As always, my pleasure!

请先登录，再进行评论。

请先登录，再回答此问题。

采纳的回答

Star Strider 2023-11-30

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/2054152-how-can-i-obtain-the-difference-between-two-data-stored-in-workspace#answer_1362927

If the two variables have the same number of elements, just subtract one from the other.

For example:

speed_error = reference - measured

That will give the error at each element of each vector.

If you want to get a single parameter with respect to the ‘speed_error’ vector, one option is to use the rms function to get the RMS error. To get the mean squared error, simply square the RMS result.

There are other options as well. The sum squared error is simply:

sum_squared_error = sum(speed_error.^2)

5 个评论
显示 3更早的评论隐藏 3更早的评论

saleh shlimet 2023-12-4

If the two variables do not have the same number of elements? how to find the error?

Star Strider 2023-12-4

Since they both by definition have to have the same sampling frequencies (so the differences between their respective time data are constant), the only way to calculate the error in that instance is to shorten the longer vector to the length of the shorter vector. Interpolating one ot the length of the other will not be appropriate.

请先登录，再进行评论。