gnuplot-info

[Gnuplot-info] input date format: week numbers + year

[Sebastien K. <seb...@ya...>]

Dear gnuplot users and developpers,

I want to plot a datafile were the x-axis data values are the week numbers of a year, 
stored in the datafile. I am producing the datafile from some other application, so I 
can easily change what is stored in it, if needed.

My problem is that for a given year (from september to july), week 2 is after week 
51. If I plot the following toy file:

# week;year;value
50;2013;10
51;2013;11
2;2014;12

with:
plot "datafile" using $1:$3
then week 2 will appear *before* week 51, and what I want on the x-axis is:

50   51   2

I checked out the "set format" command, but it seems to be only about format 
rendering, my problem is about input date format.

Any hint on the easiest way to do this ?

Thank you

Re: [Gnuplot-info] input date format: week numbers + year

[Hans-Bernhard B. <HBB...@T-...>]

Am 25.09.2013 19:00, schrieb Sebastien Kramm:
> # week;year;value
> 50;2013;10
> 51;2013;11
> 2;2014;12
>
> with:
> plot "datafile" using $1:$3
> then week 2 will appear *before* week 51, and what I want on the x-axis is:

Well, if you decided not to tell gnuplot in any way, shape or form, that 
this are dates, rather than ordinary numbers, how is it supposed to know 
that?  See "help time/date", and particularly "help timefmt".

You'll have to change your input format, too.  Week-of-year is not a 
supported date format.

Re: [Gnuplot-info] input date format: week numbers + year

[Sebastien K. <seb...@ya...>]

Hello,

On 09/25/2013 10:26 PM, Hans-Bernhard Bröker wrote:
> Well, if you decided not to tell gnuplot in any way, shape or form, that this are
>  dates, rather than ordinary numbers, how is it supposed to know that?

Thank you for answering. I am well aware that I need to tell gnuplot in some way that 
this is date-related data, my question was how ;-)

> See "help time/date", and particularly "help timefmt".

Indeed, the last command is what I was looking for (input date format)

> You'll have to change your input format, too.  Week-of-year is not a supported
> date format.

Ok, I will change the data in file, add a field with a valid date format that can be 
read and plotted with a correct ranking by gnuplot, and use xticslabel to have week 
numbers on the x-axis. I'll let you know..