abs function in rtf template

Hello,

I have to use "abs"  function at template level after doing all the calculation.I have tried in below ways ,but none of it is working.

1.

<?if:TRANSACTION_QTY1!='0'?>

<?xdoxslt:abs(sum(current-group()/LEDGER_AMOUNT))/abs(TRANSACTION_QTY)?>

<?end if?>

2.

<?if:TRANSACTION_QTY1!='0'?>

<?xdoxslt:abs((sum(current-group()/LEDGER_AMOUNT))/TRANSACTION_QTY)?>

<?end if?>

3.

<?if:TRANSACTION_QTY1!='0'?>

<?xdoxslt:abs(div((sum(current-group()/LEDGER_AMOUNT)),TRANSACTION_QTY))?>

<?end if?>

Thanks

Suchita