[R] Wrap column headers caption

[Felipe Carrillo]

Hi:
Using this dataframe with quite long column headers, how can I wrap the 
text so that the columns are narrower. I was trying to use strwrap without 
success. Thanks

reportDF <- structure(list(IDDate = c("3/12/2010", "3/13/2010", "3/14/2010",
"3/15/2010"), FirstRunoftheYear = c("33 (119 ? 119)", "n (0 ? 0)", "893 (110 ? 
146)",
"140 (111 ? 150)"), SecondRunoftheYear = c("33 (71 ? 71)", "n (0 ? 0)",
"337 (67 ? 74)", "140 (68 ? 84)"), ThirdRunoftheYear = c("890 (32 ? 47)",
"n (0 ? 0)", "10,602 (32 ? 52)", "2,635 (34 ? 66)"), FourthRunoftheYear = c("0 ( 
? )",
"n (0 ? 0)", "0 ( ? )", "0 ( ? )"), LastRunoftheYear = c("0 ( ? )", "n (0 ? 0)",
"0 ( ? )", "0 ( ? )")), .Names = c("IDDate", "First Run of the Year", "Second 
Run of the Year",
"Third Run of the Year", "Fourth Run of the Year", "Last Run of the Year"), 
row.names = c(NA, 4L), class = "data.frame")
 


Felipe D. Carrillo
Supervisory Fishery Biologist
Department of the Interior
US Fish & Wildlife Service
California, USA