Ralf B
2010-Mar-25 21:03 UTC
[R] Frequencies from x/y data into a 2d table (for 3d histogram or heatmap)
Hi all, I have simple x/y data from screen recording in a sequence: number,x,y ---------------- 1,10,30 1,20, 1,43,110 1,74,18 1,88,112 and would like to create a 3d histogram data structure that i can use to create a 3d histogram or, more likely a heatmap. The unterlying data structure therefore needs to look like this: 0-10 11-20 21-30 31-40 0-10 11-20 21-30 31-40 where the values in the cells represent counts of datapoints fitting respective ranges for x and y. Can somebody point me to a procedure in R that can make such a transformation for different range sizes (i.e. 10 in my example)? I came across the following method: https://stat.ethz.ch/pipermail/r-help/attachments/20070425/fcb92205/attachment.pl which seems (at least close) but did not get it running (could not find clear3d()). I also dont' need the 3d histogram plot as I will be using the table to create a heatmap. I might be thinking to complicated here. To me, it seems like this should be possible with a few lines of code. Perhaps one of you has them lying around somewhere or knows a script that does the trick. Thanks in advance! Ralf
Marcio Pupin Mello
2012-Feb-29 18:48 UTC
[R] Frequencies from x/y data into a 2d table (for 3d histogram or heatmap)
Hi Ralf, have you solved your problem?! If so, could you share? I have the same problem... Best, Marcio On 3/25/10 6:03 PM, Ralf B wrote:> Hi all, > > I have simple x/y data from screen recording in a sequence: > > number,x,y > ---------------- > 1,10,30 > 1,20, > 1,43,110 > 1,74,18 > 1,88,112 > > and would like to create a 3d histogram data structure that i can use > to create a 3d histogram or, more likely a heatmap. The unterlying > data structure therefore needs to look like this: > > 0-10 11-20 21-30 31-40 > 0-10 > 11-20 > 21-30 > 31-40 > > where the values in the cells represent counts of datapoints fitting > respective ranges for x and y. Can somebody point me to a procedure in > R that can make such a transformation for different range sizes (i.e. > 10 in my example)? I came across the following method: > > https://stat.ethz.ch/pipermail/r-help/attachments/20070425/fcb92205/attachment.pl > > > which seems (at least close) but did not get it running (could not > find clear3d()). I also dont' need the 3d histogram plot as I will be > using the table to create a heatmap. I might be thinking to > complicated here. To me, it seems like this should be possible with a > few lines of code. Perhaps one of you has them lying around somewhere > or knows a script that does the trick. > > Thanks in advance! > > Ralf >