how we can combine two time series?

madarshahian · Post by **madarshahian** » Thu Mar 11, 2010 12:34 am

Dear All;
I want to use kind of intensifying sinusoid as an excitation witch have linear trend.
I want to know how I can combine Sine Time Series which is produced by "Sine $tStart $tFinish ..." and Linear Time Series which is made by "Linear..." command.
mathematically product of these two functions is my goal, but I don't know how I can done it, using opensees and tcl/tk language.
Please guide me.
Thank you in advance also I want to say happy new year to all Iranians user of opensees in world in advance too.
:)
www.Irsasazeh.com

Post by **fmk** » Thu Mar 11, 2010 12:41 pm

you would have to do this in tcl. inside a loop that does 1 analysis step, inside each step:

1. create a load pattern with the sine wave and a factor equal to what would come from the linear series,
2. perform an analysis step,
3. remove the load pattern.

madarshahian · Post by **madarshahian** » Thu Mar 11, 2010 9:27 pm

Dear Frank;
I am not smart enough in TCL and Tk, I will try to do what you suggested, but I appreciate if you could put a simple example in Community Forum.
Best regards;
Ramin