How to match cell values across variables

I've got a table where each row is a separate result, and 2 of the variables (Qstay, indvparkingtype) in there are doubles. The 2 variables correspondingly have the same size, but differs from result to result.

Across all the results, I want to sum up the values in one variable, matched to a value in the other variable.

The variable to be matched to (indvparkingtype) has about 10 different values, let's say [1,2,3...], and I want to sum for each value of indvparkingtype, the Qstay.

So for all instances where scenarioID=1, I would want to find the total Qstay for indvparkingtype=1, =2, =3 etc.

E.g. for indvparkingtype=6, I would want to add 0.2859+0+0.4516+0+0+6.1387+0+2.3656+0.7961+... etc

And to summarise so to have the sums for all values of indvparking type