# Mathematical functions - logarithmic

Logarithmic mathematical functions operate on numeric expressions only, and will return an error if used on any other values. See also Mathematical operators.

## e()

`e()` returns the base of the natural logarithm, `e`.

Syntax:

``e()``

Returns:

 `FLOAT`
Example 1. e()
Query
``RETURN e()``

The base of the natural logarithm, `e`, is returned.

Table 1. Result
e()

`2.718281828459045`

Rows: 1

## exp()

`exp()` returns `en`, where `e` is the base of the natural logarithm, and `n` is the value of the argument expression.

Syntax:

``e(expression)``

Returns:

 `FLOAT`

Arguments:

Name Description

`expression`

A numeric expression.

Considerations:

 `exp(null)` returns `null`. `exp()` returns `Infinity` when the return value is greater than the largest `FLOAT` value (Java Double.MAX_VALUE).
Example 2. exp()
Query
``RETURN exp(2)``

`e` to the power of `2` is returned.

Table 2. Result
exp(2)

`7.38905609893065`

Rows: 1

## log()

`log()` returns the natural logarithm of a number.

Syntax:

``log(expression)``

Returns:

 `FLOAT`

Arguments:

Name Description

`expression`

A numeric expression.

Considerations:

 `log(null)` returns `null`. `log(0)` returns `-Infinity`. If (`expression` < 0), then (`log(expression)`) returns `NaN`.
Example 3. log()
Query
``RETURN log(27)``

The natural logarithm of `27` is returned.

Table 3. Result
log(27)

`3.295836866004329`

Rows: 1

## log10()

`log10()` returns the common logarithm (base 10) of a number.

Syntax:

``log10(expression)``

Returns:

 `FLOAT`

Arguments:

Name Description

`expression`

A numeric expression.

Considerations:

 `log10(null)` returns `null`. `log10(0)` returns `-Infinity`. If (`expression` < 0), then (`log10(expression)`) returns `NaN`.
Example 4. log10()
Query
``RETURN log10(27)``

The common logarithm of `27` is returned.

Table 4. Result
log10(27)

`1.4313637641589874`

Rows: 1

## sqrt()

`sqrt()` returns the square root of a number.

Syntax:

``sqrt(expression)``

Returns:

 `FLOAT`

Arguments:

Name Description

`expression`

A numeric expression.

Considerations:

 `sqrt(null)` returns `null`. If (`expression` < 0), then (`sqrt(expression)`) returns `NaN`.
Example 5. sqrt()
Query
``RETURN sqrt(256)``

The square root of `256` is returned.

Table 5. Result
sqrt(256)

`16.0`

Rows: 1