Variable changes_Telling stata to consider only 2 digits after decimal

[lal mohan kumar]

var3

0.001

0.0005

0.00006

0.01

My question is very elementary or trivial, but as I am new to Stata ,I would like to get your help. My question is that ,how can I tell stata to take only first do digits after the point. In the above case,for the first observation in var3,I require only 0.00,which is 0 itself. I dont want to try the command format as it only a display convenience.Moreover,replace var3=round(var3, 0.05) wont be helpful as it gives "(0 real changes made)" as reply. I just want to tell stata that take 2 or 3 digits after decimal.
Thanks in advance

[Clyde Schechter]

What you are asking for is, strictly speaking, impossible, because decimal numbers like 0.01 have no exact finite binary representation (just as 1/3 has no exact finite decimal representation). So when you ask Stata to deal with 0.01, it actually deals with the closest binary number to 0.01 it can find.

That said, I think the closest you can come to this would be:

gen var4 = floor(100*var3)/100

Note that I do not replace var3, since the transformation here is irreversible and information would be lost. Instead I create a new variable. If you are sure the loss of information will not come to bite you later on, you could -replace var3- instead.

[lal mohan kumar]

Thanks a lot sir