My problem is that x values increas with y until some point then the patternreverses. The whole line is a kind of U-shape with a right-buttom to middel-top diagonal at the end of it (a look at the plot makes it clearer). The interpolation (approx, spline) makes a zick-zack aut of it. What I need is to interpolate some points and to preserve the shape.
thanks in andvance René Zitat von "David Winsemius" <dwinsem...@comcast.net>:
On Jan 11, 2010, at 7:44 AM, René Mayer wrote:Dear R-users, I have a complex line by xy-values (ordered by z). And I would like to get interpolated y-values on the positions of x = 0:600. How do I get the correct points? x=c(790,790,790,790,790,786,783,778,778,766,763,761,761,761,715,628,521,350,160,134,134,129,108,101,93,111,161,249,288,243,139,45,7) y=c(606,606,606,606,606,612,617,627,627,640,641,641,641,641,689,772,877,1048,1240,1272,1272,1258,1242,1239,1239,1214,1122,959,770,479,273,133,45) z=c(0,29,58,87,116,145,174,203,232,261,290,319,348,377,406,435,464,493,522,551,580,609,638,667,696,725,754,783,812,841,870,899,928) plot(y,x,type="b")That would plot x as a function of y (the reverse of the usual convention. Is that what you want. If so, then the statement that these are ordered by z is misleading. Ordering by z would suggest that each series is a function of z. What sort of interpolation do you want and in how many dimensions?# this fails ????? lines(approx(y,x),col="blue") # with xout = c(0:600) thanks in advance, René -- Dr. rer. nat. Dipl.-Psych. René Mayer Dresden University of Technology Department of Psychology Zellescher Weg 17 D-01062 Dresden Tel.: +49-351-4633-4568 Email: ma...@psychologie.tu-dresden.de ______________________________________________ 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.David Winsemius, MD Heritage Laboratories West Hartford, CT
______________________________________________ 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.
