scatterplot of 100000 points and pdf file format
On 24-Nov-04 Prof Brian Ripley wrote:
On Wed, 24 Nov 2004 Ted.Harding at nessie.mcc.ac.uk wrote:
1. Multiply the data by some factor and then round the results to an integer (to avoid problems in step 2). Factor chosen so that the result of (4) below is satisfactory. 2. Eliminate duplicates in the result of (1). 3. Divide by the factor you used in (1). 4. Plot the result; save plot to PDF. As to how to do it in R: the critical step is (2), which with so many points could be very heavy unless done by a well-chosen procedure. I'm not expert enough to advise about that, but no doubt others are.
unique will eat that for breakfast
x <- runif(1e6) system.time(xx <- unique(round(x, 4)))
[1] 0.55 0.09 0.64 0.00 0.00
length(xx)
[1] 10001
'unique' will eat x for breakfast, indeed, but will have some trouble chewing (x,y). I still can't think of a neat way of doing that. Best wishes, Ted. -------------------------------------------------------------------- E-Mail: (Ted Harding) <Ted.Harding at nessie.mcc.ac.uk> Fax-to-email: +44 (0)870 094 0861 [NB: New number!] Date: 25-Nov-04 Time: 00:37:15 ------------------------------ XFMail ------------------------------