Loop over values not working

[David Wang]

Dear all,

I have a panel dataset (panelvar is id and timevar is year). I have been trying to generate a group of new variables from tssmooth exponential funciton using forvalues. Here is my sample data.

*To install: 
ssc install dataex, replace
clear 
input int year int id float roi
2015 1 0.069
2013 1 0.091
2012 1 0.158
2010 1 0.126
2011 1 0.162
2014 1 0.063
2014 2 -0.019
2015 2 -0.074
2015 3 0.256
2012 3 0.199
2013 3 0.229
2014 3 0.254
2010 3 0.188
2011 3 0.114
2014 4 0.07
2012 4 0.184
2013 4 0.117
2015 4 -0.033
2011 4 0.184
2010 4 0.148
2012 5 -0.007
2014 5 0.076
2010 5 1.004
2015 5 -0.021
2011 5 -0.034
2013 5 0.076
2011 6 0.129
2013 6 0.09
2015 6 0.163
2012 6 0.133
2010 6 0.132
2014 6 0.091
2013 7 0.048
2012 7 0.067
2010 7 0.019
2014 7 0.062
2011 7 0.093
2015 7 0.066
2015 8 0.125
2014 8 0.112
2011 8 0.186
2010 8 0.198
2012 8 0.131
2013 8 0.12

end

Here is my code:

xtset id year
forvalues x = 0.1(0.05)1 {
    generate `i'= 20 * `x'-1
    tssmooth exponential ewma_roi_`i' = roi, parms(`x')
}

I want to generate ewma_roi_1, ewma_roi_2, ewma_roi_3, ...., and ewma_roi_19. Each new variable corresponds to its own smoothing parameter. However, I keep receiving the error message saying "too few variables specified" (see below). To me, everything looks correct. I am not sure what the real problem is and how to fix the error of two-few-variables-specified. Any help would be greatly appreciated!

Thanks,
David

[William Lisowski]

Perhaps this does what you want.

xtset id year
forvalues i=1/19 {
    local x = `i'/20
    tssmooth exponential ewma_roi_`i' = roi, parms(`x')
}

[David Wang]

Thank you very much, William! Your code works like magic!

Best,
David