Re: [Gnuplot-info] How to directly sort data and plot

[Jian-Ming Z. <jm...@gm...>]

Hi,

Thanks for the reply. I have tried "smooth unique," but it did not work for me.

For example, the data file is shown as follow.
1 10
2 15
3 1
4 15
5 30
I want plot column 2 as y values in order of the values. That is, the
first y value is 30, the second y value is 15, the third value is 15,
and so on. I can do so by sorting the file by column 2. The file is
sorted as follows.
5 30
2 15
4 15
1 10
3 1

Then I plot the sorted file by using: plot 'datafile' using 2 w linespoints

Please kindly let me know how to use "smooth unique" to do so. Thanks.

On Fri, Aug 23, 2013 at 4:33 AM, Hans-Bernhard Bröker
<HBB...@t-...> wrote:
> On 22.08.2013 09:54, Jian-Ming Zheng wrote:
>>
>> Hi,
>>
>> I have a data file which contains several columns. The data in the
>> file are not sorted. I want to sort the data of a column (for example,
>> column 3) and plot the data. I use UNIX command sort to sort the data
>> and then use gnuplot to plot the data.
>>
>> $ sort -k3nr datafile > sortfile     # sort column 3 in decreasing order
>> gnuplot> plot 'sortfile' u 3 w linespoints     # plot sorted values of
>> column 3 at x = 0, 1, 2, …
>>
>> Is it possible to directly sort the data and plot the results in
>> gnuplot? If yes, how to do it?
>
>
> See "help smooth", then "help smooth unique".
>
>