lmo questions

lmo answers

• How to add empty row to data.table if nrow=0?
• Consolidate duplicate columns and concatenate column names
• Split data.frame by variable and apply function referring to concrete row
• simplifying R code using dplyr (or other) to rowSums while ignoring NA, unlss all is NA
• Averaging an increasing number of columns of a dataframe
• Configuring the R console so that it stops executing a list of commands whenever one command fails
• R: Find consecutive values beneath threshold
• How to replace blanks for groups of columns based on column group prefix?
• R: How to calculate mean for each row with missing values using dplyr
• How can I list only the data frame objects in R? [duplicate]