Dear Statalist, I would like to create a graph (twoway scatter) using the by() option for some groups. However, I only needed for some of the categories, not for all. I have tried using the "nofill" option, but it says that it s not possible. I do not understand why it uses all the groups and years since I am telling to each graph to use only for 2014 and 2017. Can you help me to erase those combinations in blank from the next graph?

Thanks in advance for the help.

Code:
twoway (scatter y x if inlist(time,2014,2017) & cond==1) (lfit  y x if inlist(time,2014,2017) & cond==1), by(categ time ) scheme(s2mono)
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