I need to summarize in a grouped data_frame (warn: a solution with dplyr is very much appreciated but isn't mandatory) both something on each group (simple) and the same something on "other" groups...

There must be an R-ly way to call wilcox.test over multiple observations in parallel using group_by. I've spent a good deal of time reading up on this but still can't figure out a call to wilcox.te...

I have done grouping of the grid by giving groupindex to a particular column in aspxgridview. For example, if I am grouping by means of persons name and the orders details made by that particular ...

I have a data frame like this: Date Amount Category 1 02.07.15 1 1 2 02.07.15 2 1 3 02.07.15 3 1 4 02.07.15 4 2 5 03.07.15 5 2 6 04.07.15 6 3 7 05.07.15 7 3 8 06.07.15 8 3 9 07.07.15 9 4 10...

Here's what I'm trying to do. My data frame has a factor variable, "country", and I want to split the data frame based on country. Then, I want to take the column mean over every variable for every...

I want to summarise several variables in data.table, output in wide format, output possibly as a list per variable. Since several other approaches did not work, I tried to do an outer lapply, givin...

I want to calculate the mean for each numeric variable in the following example. These need to be grouped by each factor associated with "id" and by each factor associated with"status". set.seed(1...