> ## Documentation Index
> Fetch the complete documentation index at: https://docs.honeycomb.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Math Functions in Calculated Fields

> Math functions available for calculated field formulas in Honeycomb, including SUM, AVG, CEIL, FLOOR, and arithmetic operators.

Math functions perform common mathematical operations.

## `SUM`

Evaluates to the sum of all numeric arguments.
Strings are parsed into numbers if possible, unparseable strings or other values evaluate to zero.

```ruby theme={}
# Infix operator usage: arg1 + arg2
# Examples
$serialize_ms + $scan_ms + $publish_ms
1.0 + 5 + "2.3"

# Function usage: SUM(arg1, arg2, ...)
# Examples
SUM($serialize_ms, $scan_ms, $publish_ms)
SUM(1.0, 5, "2.3")
```

## `SUB`

Evaluates to the first argument subtracted by the second, or `arg1 - arg2`.
Strings are parsed into numbers if possible, unparseable strings or other values evaluate to zero.

```ruby theme={}
# Infix operator usage: arg1 - arg2
# Examples
$serialization_ms - 100
$total_ms - ($local_ms + $merge_ms + $serialize_ms)

# Function usage: SUB(arg1, arg2)
# Examples
SUB($serialization_ms, 100)
SUB($total_ms, SUM($local_ms, $merge_ms, $serialize_ms))
```

## `MUL`

Multiplies all numeric arguments and returns the product.
Strings are parsed into numbers if possible, unparseable strings or other values evaluate to zero.

```ruby theme={}
# Infix operator usage: arg1 * arg2
# Examples
$count * $time_per_item
100 * ($json_decode_ms / $total_ms)

# Function usage: MUL(arg1, arg2, ...)
# Examples
MUL($count, $time_per_item)
MUL(100, DIV($json_decode_ms, $total_ms))
```

## `DIV`

Divides the first argument by the second, or `arg1 / arg2`.
Strings are parsed into numbers if possible, unparseable strings or other values evaluate to zero.
A division by zero evaluates to null.

```ruby theme={}
# Infix operator usage: arg1 / arg2
# Examples
$io_bytes_read / 1024
$total_ms / $rows_examined
$json_parse_time_ms / $total_request_time_ms

# Function usage: DIV(arg1, arg2)
# Examples
DIV($io_bytes_read, 1024)
DIV($total_ms, $rows_examined)
DIV($json_parse_time_ms, $total_request_time_ms)
```

## `MOD`

Computes the remainder of `arg1 / arg2`.
Strings are parsed into floats if possible, unparseable strings or other values evaluate to zero.
Evaluates to null if `arg2` is zero.

```ruby theme={}
# Infix operator usage: arg1 % arg2
# Examples
15 % 12  # 3
5.5 % 4  # 1.5
6 % 5.5  # 0.5

# Function usage: MOD(arg1, arg2)
# Examples
MOD(15, 12)  # 3
MOD(5.5, 4)  # 1.5
MOD(6, 5.5)  # 0.5
```

## `MIN`

Evaluates to the smallest argument of the same type as the first non-empty argument.
"Smallest" means the smaller, if numeric, or lexicographically first, if a string.

```ruby theme={}
# Usage: MIN(arg1, arg2, ...)
# Examples
MIN($memory_inuse_local, $memory_inuse_merge, $memory_inuse_fetch)
```

## `MAX`

Evaluates to the largest argument of the same type as the first non-empty argument.
"Largest" means the larger, if numeric, or lexicographically last, if string.

```ruby theme={}
# Usage: MAX(arg1, arg2, ...)
# Examples
MAX($mysql_latency_ms, $redis_latency_ms)
MAX(1, DIV($total_volume, $count))
```

## `LOG10`

Computes the base-10 logarithm of the argument.
Strings are parsed into numbers if possible.
Unparseable strings, and arguments less than or equal to 0, evaluate to null.

```ruby theme={}
# Usage: LOG10(arg1)
# Examples
LOG10($duration_ms)
```

## `BUCKET`

Computes discrete (categorical) bins, or buckets, to transform continuous fields into categorical ones.
This can be useful to group data into groups.
The syntax is `BUCKET( $column, size, [min, [max]])`.
The function returns `size`-sized buckets from `min` to `max`.
For example, `BUCKET( $column, 10, 0, 30)` will return groups named `< 0`, `0 - 10`, `10 - 20`, `20 - 30`, and `> 30`.

If only the `min` is specified, then the function will run without an upper bound; if neither a `min` nor `max` is specified, then the function will run without either bound, starting from a bucket `0 - size`.

In all versions, points on the boundary between two bins will fall into the lower bin.
The size, min, and max may not be columns.
If the column is not a float value, the function returns null.

```ruby theme={}
# Usage: BUCKET( $column, size, [min, [max]])
# Examples
BUCKET($duration_ms, 500, 0, 3000) # size, min and max
BUCKET($current_budget, 10, -5) # min only
BUCKET($num_users, 10) # size only
```