Greetings
I'm attempting to insert missing data on the smallest size class of
cave cricket instars into a data frame. The data involve censusing
photoplots (plots) of roosting cave crickets in which we discern in four
instars or size classes. I need to insert data on size class one into a
data frame that already has data on size classes two through four. The
data can be merged by their cave name, year, month, region (near or far
from cave entrance), plot #, and Individual (IndID). For example:
(Embedded image moved to file: pic14606.jpg)
As one example, I have data for size class (SC) one I can insert after
IndID #4 in the data above. However, when I attempt to merge these two
data frames using the following commands:
"Hs.full.anal<-merge(Hs.short.missgval,SC1_0608,
byx=c(Cave,Year,Month,Region,Plot,IndID),
byy=c(Cave,Year,Month,Region,Plot,IndID))"
I get the following message:
"WARNING: Warning in `[<-.factor`(`*tmp*`, ri, value = c(1L, 1L, 1L, 1L,
1L, 1L, 1L, :
invalid factor level, NAs generated"
Can anyone tell me what this means and how I might fix it?
Cheers
Kurt
***************************************************************
Kurt Lewis Helf, Ph.D.
Ecologist
EEO Counselor
National Park Service
Cumberland Piedmont Network
P.O. Box 8
Mammoth Cave, KY 42259
Ph: 270-758-2163
Lab: 270-758-2151
Fax: 270-758-2609
****************************************************************
Science, in constantly seeking real explanations, reveals the true majesty
of our world in all its complexity.
-Richard Dawkins
The scientific tradition is distinguished from the pre-scientific tradition
in having two layers. Like the latter it passes on its theories but it
also passes on a critical attitude towards them. The theories are passed
on not as dogmas but rather with the challenge to discuss them and improve
upon them.
-Karl Popper
...consider yourself a guest in the home of other creatures as significant
as yourself.
-Wayside at Wilderness Threshold in McKittrick Canyon, Guadalupe Mountains
National Park, TX
Cumberland Piedmont Network (CUPN) Homepage:
http://tiny.cc/e7cdx
CUPN Forest Pest Monitoring Website:
http://bit.ly/9rhUZQ
CUPN Cave Cricket Monitoring Website:
http://tiny.cc/ntcql
CUPN Cave Aquatic Biota Monitoring Website:
http://tiny.cc/n2z1o
On Wed, Nov 10, 2010 at 1:38 PM, <Kurt_Helf at nps.gov> wrote:> > Greetings > ? ? I'm attempting to insert missing data on the smallest size class of > cave cricket instars into a data frame. The data involve censusing > photoplots (plots) of roosting cave crickets in which we discern in four > instars or size classes. ?I need to insert data on size class one into a > data frame that already has data on size classes two through four. ?The > data can be merged by their cave name, year, month, region (near or far > from cave entrance), plot #, and Individual (IndID). ?For example: > (Embedded image moved to file: pic14606.jpg) > > As one example, I have data for size class (SC) one I can insert after > IndID #4 in the data above. ?However, when I attempt to merge these two > data frames using the following commands: > "Hs.full.anal<-merge(Hs.short.missgval,SC1_0608, > ? ? ?byx=c(Cave,Year,Month,Region,Plot,IndID), > ? ? ?byy=c(Cave,Year,Month,Region,Plot,IndID))" > I get the following message: > "WARNING: Warning in `[<-.factor`(`*tmp*`, ri, value = c(1L, 1L, 1L, 1L, > 1L, 1L, 1L, ?: > ?invalid factor level, NAs generated"Hard to say with the level of detail you provided, but chances are that your data are converted (internally) to factors. If not too inconvenient, I would quit the R session without saving anything, restart and type options(stringsAsFactors=FALSE) before running anything. This prevents storing of character vectors as factors. If you already have a data frame that stores factors, you can try something along the lines of newFrame = apply(frame, 2, as.character) Hope this helps, Peter