/*<pre><b>
/ Program   : equals.sas
/ Version   : 1.0
/ Author    : Roland Rashleigh-Berry
/ Date      : 31-Jul-2007
/ Purpose   : In-datastep function-style macro to compare two numeric values to
/             find if they are equal or very nearly equal.
/ SubMacros : none
/ Notes     : This technique was copied from the SAS Technical Support site but
/             amended slightly. You use it in a data step. You can get very
/             slight differences in values depending how a value was arrived at
/             but they will be very close. This code will compare them but allow
/             for tiny differences.
/ Usage     : if %equals(val1,7.3) then ...
/ 
/===============================================================================
/ PARAMETERS:
/-------name------- -------------------------description------------------------
/ val1              (pos) First value for comparison (can be text or a variable)
/ val2              (pos) Second value for comparison (text or a variable)
/===============================================================================
/ AMENDMENT HISTORY:
/ init --date-- mod-id ----------------------description------------------------
/ rrb  29Mar07         Put out "macro called" message plus header tidy
/ rrb  31Jul07         Header tidy
/===============================================================================
/ This is public domain software. No guarantee as to suitability or accuracy is
/ given or implied. User uses this code entirely at their own risk.
/=============================================================================*/

%put MACRO CALLED: equals v1.0;

%macro equals(val1,val2);
(abs(&val1-&val2) LE 1E-15*max(abs(&val1),abs(&val2)))
%mend;