Math Functions within Custom Prints (Advanced)

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Use math functions in your custom print template to calculate totals, combine number field values, count rows, and apply formatting logic directly in the printed output.

Before you start

  • Read Set up a custom print for a form first. This article assumes you are familiar with placeholder codes and tablerow syntax.
  • Math functions are used inside your Word or Excel template alongside your placeholder codes.
  • Number fields in your form are the primary use case. Make sure the questions you want to calculate are Number Field type.

Basic math operators

You can perform calculations directly between two number field values using standard operators. Place the expression inside curly braces where you want the result to appear in your template.

Operator Syntax Description
Add {$id1 + $id2} Sum of two number fields
Subtract {$id1 - $id2} Difference between two number fields
Multiply {$id1 * $id2} Product of two number fields
Divide {$id1 / $id2} First field divided by second
Round {$id1|round:2} Round to N decimal places
Ceil {$id1|ceil} Round up to nearest whole number
Floor {$id1|floor} Round down to nearest whole number
Abs {$id1|abs} Absolute value (remove negative sign)
Min {$id1|min:$id2} Return the smaller of two values
Max {$id1|max:$id2} Return the larger of two values
Sqrt {$id1|sqrt} Square root
Pow {$id1|pow:2} Raise to a power (e.g. squared)
Pi {$smarty.const.M_PI} Mathematical constant pi (3.14159...)

Worked examples

  • Add two fields: {$id2 + $id3}  outputs the sum of Question 2 and Question 3
  • Multiply two fields: {$id2 * $id3}  outputs Question 2 multiplied by Question 3
  • Round to 2 decimal places: {$id2|round:2}  outputs the value of Question 2 rounded to 2 decimal places

How it works

Declare a variable before the table and set it to 0. Inside the tablerow loop, add each row's value to the variable. After the table, output the variable to display the total.

Step 1: Initialise the variable before your table

{$value = 0}


Step 2: Inside your tablerow, accumulate each row's value

$id4 = the group question, $_row.data.id3 = Number Value #3 inside the group

{tablerow from=$id4 item=_row}

  {$_row.data.id1}  |  {$_row.data.id2}  |  {$value = $value + $_row.data.id3}{$_row.data.id3}

{/tablerow}

 

Step 3: After the table, output the running total

Total of all Number Value #3: {$value}

How the code spans table cells in Word

  1. The tablerow code must be split across the cells of your Word table row, not placed in a single cell.
  2. Place the opening tag and first field code in the first column cell.
  3. Place each subsequent field code in its corresponding column cell.
  4. Place the closing {/tablerow} tag at the end of the last column cell.

Here is how each example looks as a Word table. The code is split across cells matching your column layout:

Running total template

{$value = 0}  (place this above the table)

Question Group, Multiple Response
Worker Name Yes/No? Number Value #3

{tablerow from=$id4 item=_row}

{$_row.data.id1}

 {$_row.data.id2}

{$value = $value + $_row.data.id3}

{$_row.data.id3}{/tablerow}

Total of all Number Value #3: {$value}  (place this below the table)

 

Counter template

Counter Start = {counter start=0 skip=1 direction=up}  (place this above the table)

Question Group, Multiple Response
Count # Yes/No? Number Value #3

{tablerow from=$id4 item=_row}

Counter = {counter}

 {$_row.data.id2}

{$value = $value + $_row.data.id3}

{$_row.data.id3}{/tablerow}

 

Cycle template

Question Group, Multiple Response
Cycle # Yes/No? Number Value #3
{tablerow from=$id4 item=_row}Cycle = {cycle values="odd,even"} {$_row.data.id2}

{$value = $value + $_row.data.id3}

{$_row.data.id3}{/tablerow}

 

Example: summing hours across workers

The form used in this example has four questions:

  • Q2: Number Value #1 ({$id2}) — a number field
  • Q3: Number Value #2 ({$id3}) — a number field
  • Q4: Question Group ({$id4}) — a group question with multiple answers enabled, containing:
  •    Q4.1: Worker Name ({$_row.data.id1}) — a text field
  •    Q4.2: Did you Train? ({$_row.data.id2}) — a multiple choice Yes/No field
  •    Q4.3: Number Value #3 ({$_row.data.id3}) — a number field

Screenshot 2025-03-25 at 2.29.23 PM.png

The form used in this example: Q2 and Q3 are standalone number fields. Q4 is a Question Group with multiple answers enabled, containing Worker Name, Did you Train?, and Number Value #3.

 

Using these values entered in the form:

  • Number Value #1 (Q2): 10
  • Number Value #2 (Q3): 15
  • Group responses: Worker 1 / Yes / 8, Worker 2 / No / 10, Worker 3 / No / 12

The template code produces:

Worker Name Yes/No? Number Value #3
Worker 1 Yes 8
Worker 2 No 10
Worker 3 No 12

The group question table with each worker's response. Number Value #3 is accumulated into {$value} on each row.

After the table: Total of all Number Value #3 responses: 30

 

Counter

Counter automatically increments or decrements a number on each iteration of a tablerow loop. Use it to add a row number or sequence number to each row in a repeating group question.

When to use Counter

  • Use Counter when you want to number rows automatically, for example Row 1, Row 2, Row 3, without manually entering a number in the form.
  • Counter does not use form data. It is a template-side counter only.

Syntax

Initialise before the table:

Counter Start = {counter start=0 skip=1 direction=up}

 

Inside the tablerow, call {counter} on each row:

{tablerow from=$id4 item=_row}

  Counter = {counter}  |  {$_row.data.id2}  |  {$value = $value + $_row.data.id3}{$_row.data.id3}

{/tablerow}
  • start: the starting value of the counter (e.g. 0 starts from 0, outputs 1 on first row)
  • skip: how much to increment on each row (e.g. skip=1 counts 1, 2, 3; skip=2 counts 2, 4, 6)
  • direction: up increments, down decrements

Example output

Count # Yes/No? Number Value #3
Counter = 1 Yes 8
Counter = 2 No 10
Counter = 3 No 12

Counter automatically numbers each row as the tablerow loop iterates.

 

Cycle

Cycle alternates between a set of values on each row of a tablerow loop. Use it to apply alternating labels, colours, or categories to rows, for example alternating odd and even row labels for visual distinction.

When to use Cycle

  • Use Cycle when you want to alternate a value on each row, for example tagging rows as odd/even, or rotating through a set of labels.
  • Cycle does not use form data. It cycles through the values you define in the template.

Syntax

Inside a tablerow, define the values to cycle through:

$id4 = the group question

{tablerow from=$id4 item=_row}

  Cycle = {cycle values="odd,even"}  |  {$_row.data.id2}  |  {$_row.data.id3}

{/tablerow}
  • values: a comma-separated list of values to cycle through on each row
  • advance: set to y (default) to move to the next value on each iteration, or n to stay on the same value
  • delimiter: the character separating values (default is comma)

Example output

Cycle # Yes/No? Number Value #3
Cycle = odd Yes 8
Cycle = even No 10
Cycle = odd No 12

Cycle alternates between odd and even on each row of the group question.

 

Things to know

  • Math expressions work on Number Field question types. Text fields and other question types will not produce numeric output.
  • Running total variables ({$value = 0} pattern) must be declared before the tablerow block, not inside it.
  • The variable name ($value in the examples) can be anything you choose as long as it is consistent throughout the template.
  • Counter and Cycle are template-side functions only. They do not read from form data.
  • Dividing by zero will produce an error in the output. Add conditional logic if a divisor field might be empty.

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