LOG

Returns the logarithm of the given argument in the given base. If only one argument is given, this function returns the “natural” logarithm to base e.

Syntax

LOG ( base, number )
LOG ( number )

Arguments

  • base: the base of the logarithm.
  • number: the number to take the logarithm of.
Info

log(n) is an alias for ln(n).

log(b, n) is equivalent to ln(n) / ln(b).

Return Type

Float or double. If number is less than or equal to 0, or if base is non-positive or 1, returns NULL.

Examples

memsql> select log(2, 16);
+------------+
| log(2, 16) |
+------------+
|          4 |
+------------+

memsql> select log(2, 1234);
+-------------------+
| log(2, 1234)      |
+-------------------+
| 10.26912667914942 |
+-------------------+

memsql> select log(1234);
+--------------------+
| log(1234)          |
+--------------------+
| 7.1180162044653335 |
+--------------------+

memsql> select ln(1234);
+--------------------+
| ln(1234)           |
+--------------------+
| 7.1180162044653335 |
+--------------------+

memsql> select log(10, 1000), ln(1000) / ln(10);
+--------------------+--------------------+
| log(10, 1000)      | ln(1000) / ln(10)  |
+--------------------+--------------------+
| 2.9999999999999996 | 2.9999999999999996 |
+--------------------+--------------------+

memsql> select log(-9);
+---------+
| log(-9) |
+---------+
|    NULL |
+---------+
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