I am trying to compute GPA from class grades(which have been normallized)
I have for example the following matrix

Master =
SID    B2A    B2B    B2C   C2A     C2B    C2C    C118A    C118B     C118C
001    0.01    0.5      -0.4    1.2       -1.8     0.3      -0.3       0.4
          0.5
002    0.01    0.5      -0.4    0.5       -0.4     1.2      -1.8       0.3
          -0.3
003    0.04    0.05     0.5    -0.4     - 0.5     0.4      -1.2       1.8
        0.3
etc

Where each column has a zero mean and a standard deviation of 1.  I want to
calculate a weighted average for each row(student ID) that takes into
account that
B2A, C118A, C118B, and C118C are all 4 unit classes, and the rest, B2B,
B2C, C2A,C2B,C2C are 5 unit classes

I have tried
Units<-c(4,5,5,5,5,5,4,4,4)
Master$zGPA <-weighted.means(Master[,2:10],Units)

But that gets me one number and not a vector.

	[[alternative HTML version deleted]]

