graphing battery_bench (linux)

[evol__]

Just thought someone might find this useful. I've been running into some trouble when using rockbox, the player randomly locks up and I've been doing various things to try and pinpoint the problem. But that's another topic..

Anyway last night I left the player on to see what the batterybench plugin revealed. After checking through battery_bench.txt I figured it could be made a lot more readable if it was converted into a graph. And hey, everyone loves graphs.

To do this:

First you need to get gnuplot to (contain your shock) plot the graphs.

After copying battery_bench.txt to your ~/ we need to make it understandable for gnuplot.

So we run the following command:

cut -c1-8,22-25 battery_bench.txt > cut.txt

Basically this removes all text except the Time & Percentage left fields* and then outputs those two fields into a file called cut.txt.

Then we can run gnuplot with the following little script I cobbled together:

set terminal png small
set output 'batterygraph.png
set title "iRiver H10 Battery Performance"
set ylabel "(Charge %)"
set xlabel "(Hours)"
set xdata time          # The x axis data is time
set timefmt "%H:%M:%S"  # The times in the file look like 23:59:59
set format x "%H:%M"    # On the x-axis, we want tics like 23:59
plot "~/gnuplot/cut.txt" using 1:2 notitle with line

So save this as batterybench.gp

Now to run with gnuplot:

gnuplot batterybench.gp

This will create a png file called batterygraph.png, and here it is:


*Some of the info text at the top of battery_bench.txt is kept, but gnuplot ignores it