[Gnuplot-info] Frequency-smooth plotting for very small bins

[Pavel S. <ps...@tw...>]

Hi,

I have been trying to plot frequency-like plot for my data
but failed with both smooth kdensity/frequency approaches.

The input data are in the range of 0-15000, each value
can be present multiple times.
I tried to use the traditional trick for histogram plotting:

bw=10
set boxwidth bw
bin(x, width) = width*floor(x/width) + bw/2.0

plot [0:15000]"data" u (bin(\$1, bw)):(1.0) smooth freq w boxes

The problem is that instead of boxes I need just top line connecting the middle
point of each histogram bin. Of course, just using "with lines" in the above
won't work - in case some bin is empty, the line does not go to zero but
connects to first nonempty bin, which gives wrong result.

Any idea how to workaround this?

I tried to use smooth kdensity, which would give me similar enough
representation but clearly bandwidths like 1,5,10 are too small for ranges
around 10^5 and the output graph is just garbage.
I guess that's because I got under sampling frequency used by some
interpolation functions behind the scenes. Any way how could I increase
that sampling value?

Thanks for any hints,
Pavel