topic Formula for FPC elements in functional data explorer in Discussions

Formula for FPC elements in functional data explorer

Tntj — Thu, 08 Jun 2023 16:34:15 GMT

I have a question regarding the FPC elements in the Functional Data Explorer. Is there any way that I can extract the formula for those elements? I can only see the formula for the shape functions when I extract the FPCA Model summaries.

Re: Formula for FPC elements in functional data explorer

Elodie_Delclaux — Wed, 22 Feb 2023 14:43:30 GMT

Hi,

It isn't completely straight forward but can be done in a few steps:

1) First, extract the formula by first saving the summaries:

2) From the summary table, you can find all of the Shape Function formulas within the hidden columns of the table:

3) Clicking on the + symbol will open the Formula editor for that column, showing the formula. Double-clicking on it will display it in JSL, which can then be selected and copied:

4) Next, create a new column in your original table, or in a new table with the independent variable in another column (in my case, Time):

5) You can now explore the function in more detail, for example, by plotting it in Graph Builder if you wanted:

Does this do what you were hoping for?

Re: Formula for FPC elements in functional data explorer

Tntj — Fri, 24 Feb 2023 08:00:17 GMT

Thanks for your reply Elodie. But my question was mainly about the FPC components and the formula to calculate them if I know the shape functions. I have a case that I want to extract the shape functions from some historical data and then use that shape functions to calculate the FPC elements of a new batch. Is there any way around it?

Re: Formula for FPC elements in functional data explorer

ih — Fri, 24 Feb 2023 22:51:46 GMT

Unfortunately I do not know of an easy or straight forward way to do this, although I have many similar use cases.

@Bill_Worley this fits in with our conversation.