Re: Re: ListPlot with missing values
- To: mathgroup at smc.vnet.net
- Subject: [mg22481] Re: [mg22419] Re: ListPlot with missing values
- From: "Christopher French" <clfrench at msn.com>
- Date: Wed, 8 Mar 2000 02:22:20 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
Roy,
functions that appropriately filter out Null points and join runs of
non-Null points for Line can be added directly within ListPlot.
alist = {{1, 1}, {2, 3}, {3,5},{4,}, {5, 6}, {6,8},{7,}, {8,10},{9, 12}};
alist
//ListPlot[DeleteCases[#,{_,Null}]
,Epilog->
(#
//Split[#,And[#1[[2]]=!=Null,#2[[2]]=!=Null]&]&
//DeleteCases[#,{{_,Null}}]&
//Line/@#&
)]&
Just for fun try writing a Rule that does
eleteCases[ Split[#,FreeQ[{##},Null]&] ,{{_,Null}}]&
Christopher Lee French
<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>
The secret of magnetism, now explain that to me!
There is no greater secret, except love and hate.
Johann Wolfgang Von Gothe
-----Original Message-----
From: Roy Mendelssohn <rmendels at pfeg.noaa.gov>
To: mathgroup at smc.vnet.net
Subject: [mg22481] [mg22419] Re: ListPlot with missing values
>First, thanks to all who answered. I clearly didn't explain the problem
>carefully enough. Assume we are plotting a time series with missing
>data, and only want to conect consecutive points that have data, have
>blanks whenever a time point is missing, and still want points lined up
>correctly in time on the x axis. If I just delete cases, then the
>endpoints of any missing segment will be connected, rather than being
>blank.
>
>In the example
>
>alist = {{1, 1}, {2, 3}, {3,5},{4,}, {5, 6}, {6,8},{7,}, {8,10},{9, 12}}
>
>I want a line joing the first three points, then a blank, then a line
>connecting the next two points, then a blank etc.
>
>The reason I mentioned the number of datapoints is because one solution
>is to draw a graph for each uninterrupted segment of the time series,
>and then overlay them. This seems inelegant,because several hundred
>separate graphs might have to be drawn.
>
>If anyone else has other suggestions I would welcome them.
>
>-Roy M.
>
>
>
>