I had a tiddler containing receipt details from a number of transactions, but no other links.
So I used the [[*]] editor toolbar button to wrap the numbers there in
eg;
Amount
$[[713.59]]
Then I used the following to add them all up
{{{ [all[current]links[]sum[]] }}}
Result: all the numbers in the current tiddler are summed up and gives me the grand total
Ideas;
A macro that collects all links in a tiddler, separating out only numbers then provides a count, sum and average. Perhaps even other useful values.
A not link enabled parsing of a tiddler to retrieve the same.