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reversing calculation order [message #4087]

Mon, 24 April 1995 00:00

rclark
Messages: 12
Registered: September 1992

Junior Member

I need to fill in some values for a vector from a recurrence relation.

V(0:N-1) = func(V(1:*)) ;I wish there was a shorthand for (*-1)

Where V(N) is the only value initially defined (Well actually it is
calculated from an ascending recurrence relation but the values of
V(0:N-1) from that step are of no further interest. The results of the
second recurrence are the ones returned.)

I know that ROTATE can be used to reverse the order of the vector for the
calculation, and then reverse them again to put it back in the right
order. But is it possible to eliminate these two reverse operations and do
the calculation in backwards direction? (no FOR loops, too slow!)

The vector is fairly short but this function will get called a lot.

Richard Clark
rclark@lpl.arizona.edu
--
Still working on the other 999 lines.

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[Message index]

		reversing calculation order By: rclark on Mon, 24 April 1995 00:00
		Re: reversing calculation order By: Fergus Gallagher on Thu, 04 May 1995 00:00
		Re: reversing calculation order By: amaravad on Fri, 05 May 1995 00:00

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