You can use the following smart fields in your templates to do maths operations:
addition – addition
sub – subtraction
mul – multiplication
div – division
intdiv – integer (floor) division
abs – absolute value
mod – modulo
Examples:
{{ 17|sub:13 }}
would return 4 (because 17 minus 13 equals to 4)
The following is a complex example combining math operations on the balance of the invoice attached:
{% with invoices.0.balance|mul:0.01|floatformat:2 as variable_interest %}
{% with invoices.0.balance|addition:10 as interest_fixed %}
The 1% variable interest is: ${{ variable_interest }}
The $10 fixed interest is: ${{ interest_fixed }}
The total interest is: ${{ variable_interest|addition:interest_fixed }}
{% endwith %}
{% endwith %}
First line: applying 1% on the balance of the invoice, and ensuring a rounding to 2 decimals in a variable variable_interest
Second line: applying $10 fixed interest rate
Fifth line: adding both variable and fixed interests
If the invoice balance is $4200, then the final result of the example above would be:
The 1% variable interest is: $42.00
The $10 fixed interest is: $4,210.00
The total interest is: $4,252.00