could someone please help me. I'm trying to create a simple chart.

```
set datafile separator ","
set xdata time   
set timefmt "%d/%m/%Y %H:%M:%S" 
set format x "%H:%M" 
set autoscale y
plot ["13:00":"14:00"] './data.csv' using 1:2 with lines

```

data.csv:

```
26/10/2010 13:30:01,1

26/10/2010 13:30:12,2

26/10/2010 13:30:23,3

26/10/2010 13:30:34,4

```

gives me the error:

```
line 6: all points y value undefined!

```

I've tried all manners of timefmt settings!

Many thanks