log
If there is only one argument, then this takes the natural logarithm of the argument. Supports Spark Connect.
For the corresponding Databricks SQL function, see log function.
Syntax
Python
from pyspark.sql import functions as dbf
dbf.log(arg1=<arg1>, arg2=<arg2>)
Parameters
Parameter | Type | Description |
|---|---|---|
|
| base number or actual number (in this case base is |
|
| number to calculate logariphm for. |
Returns
pyspark.sql.Column: logariphm of given value.
Examples
Python
from pyspark.sql import functions as dbf
df = spark.sql("SELECT * FROM VALUES (1), (2), (4) AS t(value)")
df.select("*", dbf.log(2.0, df.value)).show()
Output
+-----+---------------+
|value|LOG(2.0, value)|
+-----+---------------+
| 1| 0.0|
| 2| 1.0|
| 4| 2.0|
+-----+---------------+
Python
from pyspark.sql import functions as dbf
df = spark.sql("SELECT * FROM VALUES (1), (2), (0), (-1), (NULL) AS t(value)")
df.select("*", dbf.log(3.0, df.value)).show()
Output
+-----+------------------+
|value| LOG(3.0, value)|
+-----+------------------+
| 1| 0.0|
| 2|0.6309297535714...|
| 0| NULL|
| -1| NULL|
| NULL| NULL|
+-----+------------------+