[BioC] xy-plot of fcs fails: undefined column selected

[Tobias Timmel [guest]]

Dear Bioconductor community,

I've just started to process my flow cytometry data with the R Bioconductor packages. After reading a fcs file into a flowFrame I tried to make an xy-plot: 

---8<---
library(flowCore)
library(flowViz)
sample <- read.FCS("sample.fcs", transformation=FALSE)
xyplot("SSC-A" ~ "FSC-A", data=sample)
---8<---

Plotting fails and I get the following error: 

Error in `[.data.frame`(ranges, , channel.x.name) : 
  undefined columns selected

When playing around with the provided example data (GvHD), however, xy-plots are fine. 

Any idea how to solve this problem? Is it a matter of my fcs file? It's a standard export from an FACSCanto2 machine using FacsDiva software.

Best regards,
Tobias
-- 
 Dr. Tobias Timmel
 Muscle Research Unit
 Experimental and Clinical Research Center (ECRC)
 Charité Universitätsmedizin Berlin and Max Delbrück Center Berlin

 -- output of sessionInfo(): 

R version 3.1.0 (2014-04-10)
Platform: x86_64-pc-linux-gnu (64-bit)

locale:
 [1] LC_CTYPE=de_DE.UTF-8       LC_NUMERIC=C               LC_TIME=de_DE.UTF-8        LC_COLLATE=de_DE.UTF-8     LC_MONETARY=de_DE.UTF-8   
 [6] LC_MESSAGES=de_DE.UTF-8    LC_PAPER=de_DE.UTF-8       LC_NAME=C                  LC_ADDRESS=C               LC_TELEPHONE=C            
[11] LC_MEASUREMENT=de_DE.UTF-8 LC_IDENTIFICATION=C       

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
[1] flowViz_1.28.22 lattice_0.20-29 flowCore_1.30.7

loaded via a namespace (and not attached):
 [1] Biobase_2.24.0      BiocGenerics_0.10.0 corpcor_1.6.6       DEoptimR_1.0-1      graph_1.42.0        grid_3.1.0          hexbin_1.26.3      
 [8] IDPmisc_1.1.17      KernSmooth_2.23-12  latticeExtra_0.6-26 MASS_7.3-33         mvtnorm_0.9-9995    parallel_3.1.0      pcaPP_1.9-49       
[15] RColorBrewer_1.0-5  robustbase_0.91-1   rrcov_1.3-4         stats4_3.1.0        tools_3.1.0   

--
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