I have a dataset looks like this
time value
0.1 2
0.1 3
0.2 2
0.2 4
0.2 1
I also have a threshold value threshold = 2.5
I want to combine the rows with the same time point and calculate the ratio above the threshold and return a table like this:
time value
0.1 0.50
0.2 0.33
I have tried to use data.table to combine all the rows with same time points but I am having some trouble to come up a function to calculate ratio at each time point. I know that I could write some for loop but I am wondering if there's a more R way to solve this problem.
My thought is something like this:
results <- dt[,some_function(value, threshold),by=time]
Thank you in advance.
