[Gnuplot-info] gnuplot xtic question

[Jonathan L. <jl...@fr...>]

I have data as follows which I want to plot in gnuplot. The first column
has floating point data which corresponds to the time of day in seconds
with microsecond precision. eg 58765.941980 corresponds to
16:19:25.941980. (hours:mins:sec.micro). The 2nd column corresponds to
network latency in microseconds.

58765.941980    0.151529
58766.547128    0.151253
58766.649092    0.135645
58766.751071    0.101977
58766.853054    0.113067
58766.955028    0.141189
58767.715886    0.154117
58767.817853    0.156928
58767.919834    0.146146
58768.021811    0.114410

There are potentially ten data points in the space of a second. If i
express time in the format 16:19:25.941980 the graph is inaccurate
because gnuplot does not support fractions of a second due to using the
tm structure.

So Im going to stick to plotting the floating point data. Gnuplot
generates tics on the x-axis and labels them. What is the algorithm
where gnuplot calculates where the tics should be?

I could write a C program to parse through the data file and generate a
file with gnuplot commands. if i knew exactly where the tics were going
to be I could put some tics manually eg.
set xtics ("16:19:25",58765.0, 16:19:30",58770.0) and so on. So that the
X axis would have labels with time values.

So my question again is 
What is the algorithm where gnuplot calculates where the tics for
floating point data on the x-axis should be?

I would appreciate and replys 
Jonathan Lynch