Tena koe Jerry myVars would be the unique values of Anlysis_Soil. I guess Anlysis_Soil is a factor, in which case
myVars <- levels(Anlysis_Soil) The for() loop then steps through each of these in turn. HTH .... Peter Alspach PS If you'd like more details it might be better to contact me off list. P > -----Original Message----- > From: r-help-boun...@r-project.org > [mailto:r-help-boun...@r-project.org] On Behalf Of Jerry Floren > Sent: Friday, 22 January 2010 9:53 a.m. > To: r-help@r-project.org > Subject: Re: [R] Help with subset > > > Thank you Peter. I am really new to this. The spreadsheet I > am working with has 12,379 rows with the first row consisting > of the variable names and > 12,378 rows of data. There are seven columns, and the 7th > column is the only one with numerical data ("Results"). > > I need to match up the variable Results with the variable > "Anlysis_Soil", which is the type of test performed by the > labs on one of 20 different soil samples. Here are some > examples of the Anlysis_Soil variable: > > Anlysis_Soil > Bases-Aluminum KCL Extr-2008-116 > Bases-Aluminum KCL Extr-2008-116 > Bases-Aluminum KCL Extr-2008-117 > Bases-Aluminum KCL Extr-2008-118 > Bases-Aluminum KCL Extr-2008-118 > Bases-Aluminum KCL Extr-2008-119 > Bases-Aluminum KCL Extr-2008-120 > Bases-Aluminum KCL Extr-2008-120 > Bases-Aluminum KCL Extr-2009-101 > > Actually, I am not interested in any of the above, because > there are too few (less than 9). > > I think I need to first identify the unique Anlysis_Soil from > the entire list, and I thought using "list" might work: > > > anlyses <- list(Anlysis_Soil) > > str(anlyses) > List of 1 > $ : Factor w/ 1695 levels "Bases-Aluminum KCL > Extr-2008-116",..: 1 1 2 3 3 > 4 5 5 6 6 ... > > > > It does correctly identify there are 1695 unique > "Anlysis_Soil" variables. > However, "anlyses" contains all 12,378 "Anlysis_Soil" variables. For > example: > > print(anlyses) > ... > ... > ... > [12374] Soil pH & EC-Soil EC (1to2)-2009-115 > > [12375] Soil pH & EC-Soil EC (1to2)-2009-115 > > [12376] Soil pH & EC-Soil EC (1to2)-2009-115 > > [12377] Soil pH & EC-Soil EC (1to2)-2009-115 > > [12378] Soil pH & EC-Soil EC (1to2)-2009-115 > > 1695 Levels: Bases-Aluminum KCL Extr-2008-116 ... > > And once again shows correctly that there are 1,695 unique > "Anlysis_Soil" > variables. > > Once the unique Anlysis_Soil variables are identified, I need > to determine the ones greater than 8, and I see how that > could be done with your code. > > I am not clear what you mean by, "for (myV in myVars)" ? Is > myV the name of one of the unique variables that has at least > 9 Results? Is myVars the entire column of "Anlysis_Soil" ? > > I am not sure if this is any clearer. > > Thanks, > > Jerry Floren > Minnesota Department of Agriculture > > -- > View this message in context: > http://n4.nabble.com/Help-with-subset-tp1049883p1058242.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
