identify data points by certain criteria
On Jun 12, 2013, at 5:55 PM, Ye Lin wrote:
Hey I want to identify data points by criteria, here is an example of my 1min data Time Var1 Var2 00:00 1 0 00:01 0 0 00:02 1 0 00:03 1 0 00:04 0 0 00:05 1 0 00:06 1 0 00:07 1 0 00:08 1 0 00:09 0 0 00:10 1 0 00:11 1 0 00:12 1 0 00:13 0 0 I want to identify the data points where Var1=0 and Var2=0, ( in this example shud be the points highlighted above), then calculate the time duration between these data points, (in this example, shud be 3min, 5 min and 4min), then identify the starting point of the max time duration ( in this example shud be the starting point of 5-min-duration, return the data points at 00:09), finally return the value in "Time" column ( in this example shud be "00:09")
While you are waiting for an answer you might want to read the Posting Guide: http://www.R-project.org/posting-guide.html Points to pay special attention to: Plain-text. Posting code. Posting examples in form that can be pasted into console session (dump or dput functions). Providing context for problem (such as describing the conventions for your time-scale) and your background (since this looks like a homework exercise.)
Thanks for your help! [[alternative HTML version deleted]]
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David Winsemius Alameda, CA, USA