Thomas questions

• Combine/merge columns while avoiding NA?
• How to match 1 column to 2 columns?
• ggplot2: Tick labels as base e exponents
• ggplot2 2.1.0 broke my code? Secondary transformed axis now appears incorrectly
• R - How to apply different functions to certain rows in a column
• Create category based on range in R
• How to use italics for facet labels in ggplot2?
• How to calculate difference from initial value for each group in R?
• How to filter/subset a data.frame using values from one of its column [duplicate]
• How to assign "cut" range midpoints in R?

Thomas answers