Re: Decimal Compare not working

[Hans Brost]

There are some other considerations and it won't work unless you do the following.

Say you set local variables from a DB Row like this (both values are the same (-0.00003) in the DB):

$MstMACD = $MstNxtRow['MACD']; is -0.00003
$MstMACDPrev = $MstNxtRow['MACDPrev']; is -0.00003

$MstD1Pri is .001
$MstMA12 is .00103,
$MstMA26 is .00106

Then calculate a new $MstMACD (which will also calculate to -0.00003):

$WkEMA = (($MstD1Pri - $MstMA12) * 0.1538461) + $MstMA12;
$MstMA12 = round($WkEMA, 5);

$WkEMA = (($MstD1Pri - $MstMA26) * 0.074074) + $MstMA26;
$MstMA26 = round($WkEMA, 5);


$MstMACD = $MstMA12 - $MstMA26;

And to all appearances $MstPrevMACD is the SAME as $MstMACD, a comparison of the 2 for equality will FAIL unless you do this:

$WkEMA = $MstMA12 - $MstMA26;
$MstMACD = round($WkEMA, 5);

In other words, it's not sufficient to round the MA12 and MA26 to 5 decimals, and expect the result of a subtraction to also be 5 decimal places.

Clear as mud I'm sure.....lol.......z