Hi R users,

Is there an easy way in R to generate the results table below using table 1
and the formula (simplified version of the real problem)?  It would be easy
if I knew the R equivalent of SAS's retain function, but could not find one.

Thanks in Advance for any help!

table1:

ID      X2         X3
1.00    1.00       0
2.00    0.00    
3.00    1.00    
4.00    3058    
5.00    0.00    
6.00    6.00    

Formula: X3 = x2 + (.24 * x3)
                
where the values in the x3 column of the result table are retained from
previous x3 rows.. Also the first x3 value is initialized to 0 to start

e.g.
        for ID=1 we have  1 + .24(0)                    = 1.00          
        for ID=2 we have  0 + .24(1)                    = 0.24
        for ID=3 we have  1 + .24(.24)          = 1.06
        for ID=4 we have  3058 + .24(1.06)      = 3058.25
        etc.............

Results:
ID      X2      x3
1.00    1.00    1.00
2.00    0.00    0.24
3.00    1.00    1.06
4.00    3058    3058.25
5.00    0.00    733.98
6.00    6.00    182.16
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