[R] matrix transformation into 3 columns

[Dimitrios Rizopoulos]

probably ?reshape() could be used in this case; I hope it helps.

Best,
Dimitris

-- 
Dimitris Rizopoulos
Ph.D. Student
Biostatistical Centre
School of Public Health
Catholic University of Leuven

Address: Kapucijnenvoer 35, Leuven, Belgium
Tel: +32/(0)16/336899
Fax: +32/(0)16/337015
Web: http://med.kuleuven.be/biostat/
     http://www.student.kuleuven.be/~m0390867/dimitris.htm


Quoting Rado Bonk <rado.bonk at jrc.it>:

> Dear R-users,
> 
> I have matrix (mprecip) with headers:
> 
>  > dim(mprecip)
> [1] 6268  170
> 
>  > mprecip
>             date GilzeRijen Eindhoven Volkel ZuidLimburg Arcen
> Ubachsberg
> 1    01/01/1978         NA       0.0     NA         0.1    NA        
> NA
> 2    01/02/1978         NA       0.0     NA         0.0    NA        
> NA
> 3    01/03/1978         NA       1.9     NA         0.7    NA        
> NA
> 4    01/04/1978         NA       3.5     NA         6.9    NA       
> 6.0
> 5    01/05/1978         NA       1.6     NA         1.8    NA       
> 1.3
> 6    01/06/1978         NA       0.0     NA         0.0    NA        
> NA
> 7    01/07/1978         NA       0.0     NA         0.0    NA        
> NA
> 8    01/08/1978         NA       0.0     NA         0.0    NA        
> NA
> 
> Columns are: DATE and PRECIP values for each station listed in the
> header.
> 
> I would like to transform the matrix into three columns (database
> like) 
> to be able to load the data in the database:
> 
> STATION_NAME1 DATE PRECIP
> STATION_NAME1 DATE PRECIP
> STATION_NAME1 DATE PRECIP
> STATION_NAME1 DATE PRECIP
> .
> .
> .
> .
> STATION_NAME2 DATE PRECIP
> STATION_NAME1 DATE PRECIP.
> .
> .
> .
> STATION_NAME3 DATE PRECIP
> 
> 
> 
> 
> -- 
> Dr. Radoslav Bonk
> European Commission - DG  Joint Research Centre (JRC)
> Institute of Environment and Sustainability (IES)
> LM Unit - Natural Hazards
> Via E. Fermi, TP 261, 210 20 Ispra (VA), ITALY
> tel: 0039 0332 78 6013
> fax: 0039 0332 78 6653
> http://natural-hazards.jrc.it/floods
> 
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