1
$\begingroup$

I am in the process of writing a paper and I have a doubt. I am not sure that this is the best stackexchange site where to post since it is more a terminology problem than a mathematical one. Please point me to the right site if I am wrong.

During my experiments, I am acquiring a set of kinematic variables (angles) which we can call $x_i$ and I have a set of 5 outputs $y_i$. To each variable is associated a time-series.
Therefore, I wanted to denote the variables introduced above in the following way, but I am not sure if it is the best one.

(I need to introduce explicitly the time series because in the paper I talk about the correlation of the two time-series.)

I will write:

We denote with $\mathbf{x}=\{x_1,x_2,\dots,x_{n_x} \}$ (with $n_x=10$) the set of kinematic variables acquired at each time step, and with $\mathbf{y}=\{y_1,y_2,\dots,y_{5} \}$ the outputs. Moreover, we denote with $X_i,Y_i$ the time series respectively associated to the variable $x_i, y_i$.

Thanks for your help.

$\endgroup$
  • $\begingroup$ rate of change ? $\endgroup$ – Roddy MacPhee Apr 16 at 19:00
  • $\begingroup$ I did not understand your comment $\endgroup$ – kalmanIsAGameChanger Apr 24 at 12:31
1
$\begingroup$

There is just one choice of notations you made that I find a bit strange, but I am not saying it is compulsory to change it.

One should try not to write redundancies like $x_{n_x}$. If you want to avoid confusions between indexes and bounds (here we have $x_i$ with $i \le n_x$), you should tend to use upper cases letters without any index. So I would rather write : $\mathbf{x}=\{x_1,x_2,\dots,x_{N}\}$.

Otherwise I find your notations perfectly fine.

To write the $j$-th term of the time serie, you have plenty of choices $X_i(j), X_{ij}, X_i^{(j)}$. If the treatment of those times series involves matrix operations, $X_{ij}$ seems like a very good choice.

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.