Log10¶

Overview¶

The Log10 expression computes the base-10 logarithm of a numeric value. It extends UnaryLogExpression and uses Java's StrictMath.log10 function to perform the calculation.

Syntax¶

LOG10(expr)

import org.apache.spark.sql.functions.log10
log10(col("column_name"))

Arguments¶

Argument	Type	Description
child	Expression	The numeric expression to compute the base-10 logarithm of

Return Type¶

Double - returns a double precision floating point number representing the base-10 logarithm.

Supported Data Types¶

Numeric types (Int, Long, Float, Double, Decimal)
Any expression that can be cast to a numeric type

Algorithm¶

Evaluates the child expression to get the input value
Converts the input to a double if necessary
Applies Java's StrictMath.log10 function to compute the base-10 logarithm
Returns the result as a double value
Handles null propagation through the UnaryLogExpression parent class

Partitioning Behavior¶

This expression preserves partitioning characteristics:

Does not affect data distribution or partitioning scheme
Does not require shuffle operations
Can be applied per-partition independently

Edge Cases¶

Returns null if the input expression evaluates to null
Returns NaN (Not a Number) for negative input values
Returns negative infinity for input value 0
Returns 0.0 for input value 1.0
Returns positive infinity for input value positive infinity

Code Generation¶

This expression supports Catalyst code generation (Tungsten) through its parent UnaryLogExpression class, enabling efficient compiled code execution rather than interpreted evaluation.

Examples¶

-- Basic usage
SELECT LOG10(100);
-- Returns: 2.0

-- Using with column data
SELECT LOG10(amount) FROM sales;

-- Example from source documentation
SELECT LOG10(10);
-- Returns: 1.0

// DataFrame API usage
import org.apache.spark.sql.functions.log10

df.select(log10(col("value")))

// With column transformation
df.withColumn("log10_value", log10(col("original_value")))