I am a bit confused over how Stata determines what can fit into the width of
a formatted field (the w in w.d)  All references are Stata 8 on Windows 95.
I've generally used a comma 12.0 type format to display U.S. population
counts.  But I was using %12.0gc and I got
. display %12.0gc 123456789
   123456789
I've always assumed that 12 was enough spaces for hundreds of millions
including commas.  But apparently not with the %gc format.
In comparison %fc is fine,
. display %12.0fc 123456789
 123,456,789
The reference manual (A-F) page 394 states that %11.0gc is too small for
23,667,902 to display with commas, which does appear to be the case:
. display %11.0gc 23667902
   23667902
But %11.0fc is fine:
. display %11.0fc 23667902
 23,667,902
The User's manual on page 121 states that 10,000,000 with a %9.2fc format
will display
10,000,000.00
which is clearly incorrect
. display %9.2fc 10000000
 1.00e+07
It also states (page 121) that the f format will always display the same
number of decimal places , even if there is a loss in displayed precision.
So does the gc format keep a space for the decimal, while fc does not or
what?  %11.0gc should be fine for 23667902 in my mind, as that is only TEN
required spaces as far as I can tell.  How do I calculate the number of
digits that will display with the gc format?
Bryan Sayer
Statistician, SSS Inc.
[email protected]
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