# Holding a vector value for specific time

1. Oct 4, 2011

### gryphon1221

I have been wracking my brain trying to figure this out. I have a 1xn vector I have gained through signal processing. I am multiplying it to another 1xn vector with a different scale.

the first vector Xb moves to the next value every 1/1.023e6 seconds
the second vector Xc moves to the next value every 1/1.405e6 seconds.

I am looking for a way that I can transform keep Xb's 1xn dimension, but hold the values over a sample time of 1/1.405e6 seconds. for example the first ten values of:

Xb=[-1 1 -1 -1 -1 -1 1 1 -1 -1]
Xc=[0 1.41373858718699, 0.0732749615049943, -1.40994069977540, -0.146353076113111, 1.40235512765087, 0.219038025739767, -1.39100224880207, -0.291134548504378, 1.37591256176390]

The time scale difference makes it so Xb has the same value for the first 6 values of Xc, but this is not a constant feature when comparing the vectors. Does anybody have a clue how to do this?

2. Oct 5, 2011

### gryphon1221

I looked at resample. The problem is that the Xb code is just made with modulo 2 addition and has no real time. Xc is a continuous sin(2*pi*f1*t) where f1 is a frequency at t is taken every 1/5.714286e6 seconds. Xb is just a number of discrete values (a BPSK signal).

In reality Xb changes every 1/1.023e6 seconds. I want to hold the values of Xb constant whenever t falls somewhere in between (count-1)/1.023e6<=t<count/1.023e6, where the count moves up to the next value in Xb every time t exceeds count/1.023e6