I am not trying to fit a horizontal line at every unique value of y. I am trying fit the y values with as few horizontal lines by trading off the number of horizontal lines with the error. The actual problem I am trying to solve is to smooth data in a time series. Here is a realistic example of y
y=c(134.45,141.82,143.81,141.81,145,141.61,143.72,145.71,200,175,140,200,148.77,71.64,111.57,118.15,119.15,112.8,111.64,111.64,157.26,143.8,40.19,64.99,64.99,129.98,64.99,65,64.98,64.99) An example fit for y using multiple horizontal lines (may not be the best fit in terms of squared error or another error metric, but I have included the y value for concreteness) 1. A horizontal line at approximately y=140 (to fit the first 13 values - 134.45 to 148.77) 2. A horizontal line at approximately y=110 (to fit the next 7 values - 71.64 to 111.64) 3. A horizontal line at approximately y=150 (to fit the next 2 values - 157.26 to 143.8) 4. A horizontal line at approximately y=65 (to fit the last 8 values - 40.19 to 64.99) -sashi. [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.