> question Number1: when reduce Time dimension from individual subject.
> what i choose the option -reduce or -pcsave?
Use -pcsave to specify the number of components to keep in the final dataset.
> Number2: when concatenate the reduced data from all subjects
>
> 1 and 2, any type of concatenate data?
>
> 1. A subject [0.....50] + B subject[51...100]+c subject[101...150]=150(serial)
>
> 2. A subject[0.......50]
> +
> B subject[0.......50] =150(parallel)
>+
> C subject[0.......50]
Go with serial concatenation.
Gang