'.A' in numeric field

[HenkT]

Hi,
I came acreoss some code lines where '.A' is placed into a numeric field to identify a missing value.
If you look into the created dataset there is an 'A' listed in a numeric field.
Is there some documentation\explanation with this feature?

thanks
Henk

e.g.
data test1;
length a 8 b $8;
a=1;
b='1';
output;

a=input('.A',8.);
b='A';
output;
run;

data test2;
set test1;
if a=input('.A',8.);
run;

[data_null__]

They are called special missing values. .A-.Z and ._ along with the regular missing the lone dot.


http://support.sas.com/documentation/cdl/en/lrcon/62955/HTML/default/viewer.htm#/documentation/cdl/e...