The kdensity option is a way to plot a kernel density estimate (which is a
smooth histogram) for a random collection of points, using Gaussian kernels.
A Gaussian is placed at the location of each point in the first column and
the sum of all these Gaussians is plotted as a function. The value in the
second column is taken as weight of the Gaussian. To obtain a normalized
histogram, this should be 1/number-of-points. By default gnuplot calculates
and uses the bandwidth which would be optimal for normally distributed data.
default_bandwidth = sigma * (4/3N) ** (0.2)
This will usually be a very conservative, i.e. broad bandwidth.
Alternatively, you can provide an explicit bandwidth.
plot $DATA smooth kdensity bandwidth <value> with boxes
The bandwidth used in the previous plot is stored in variable
GPVAL_KDENSITY_BANDWIDTH.
Build Daemon
2017-06-16