Report totals

A common need in reports is to provide totals. This can be done using Python expressions to compute those totals.

After the closing tag of <t t-foreach>, we will add a final row with the totals:

<!-- Report footer content -->
<div class="row">
  <div class="col-xs-3">
    Count: <t t-esc="len(docs)" /> 
  </div> 
  <div class="col-xs-2" /> 
  <div class="col-xs-1" /> 
  <div class="col-xs-3" /> 
  <div class="col-xs-3" /> 
</div> 

The len() Python statement is used to count the number of elements in a collection. Similarly, totals can also be computed using sum() over a list of values. For example, if we had an amount_cost field, we could have used the following list comprehension to compute the corresponding total:

<t t-esc="sum([o.amount_cost for o in docs])" />

You can think of list comprehensions as embedded for loops.

Sometimes, we want to perform some computations as we go along with the report, for example...