## 4.6. Mathematical functions - logarithmic

These functions all operate on numeric expressions only, and will return an error if used on any other values. See also Section 2.7.4, “Mathematical operators”.

Functions:

### 4.6.1. e()

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

Syntax: `e()`

Returns:

 A Float.

Query.

``RETURN e()``

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

Table 4.60. Result
e()

1 row

`2.718281828459045`

Try this query live.  none RETURN e()

### 4.6.2. exp()

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

Syntax: `e(expression)`

Returns:

 A Float.

Arguments:

Name Description

`expression`

A numeric expression.

Considerations:

 `exp(null)` returns `null`.

Query.

``RETURN exp(2)``

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

Table 4.61. Result
exp(2)

1 row

`7.38905609893065`

Try this query live.  none RETURN exp(2)

### 4.6.3. log()

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

Syntax: `log(expression)`

Returns:

 A Float.

Arguments:

Name Description

`expression`

A numeric expression.

Considerations:

 `log(null)` returns `null`. `log(0)` returns `null`.

Query.

``RETURN log(27)``

The natural logarithm of `27` is returned.

Table 4.62. Result
log(27)

1 row

`3.295836866004329`

Try this query live.  none RETURN log(27)

### 4.6.4. log10()

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

Syntax: `log10(expression)`

Returns:

 A Float.

Arguments:

Name Description

`expression`

A numeric expression.

Considerations:

 `log10(null)` returns `null`. `log10(0)` returns `null`.

Query.

``RETURN log10(27)``

The common logarithm of `27` is returned.

Table 4.63. Result
log10(27)

1 row

`1.4313637641589874`

Try this query live.  none RETURN log10(27)

### 4.6.5. sqrt()

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

Syntax: `sqrt(expression)`

Returns:

 A Float.

Arguments:

Name Description

`expression`

A numeric expression.

Considerations:

 `sqrt(null)` returns `null`. `sqrt()` returns `null`

Query.

``RETURN sqrt(256)``

The square root of `256` is returned.

Table 4.64. Result
sqrt(256)

1 row

`16.0`

Try this query live.  none RETURN sqrt(256)