divide (Compute)

When To Use

Use divide to divide every value of one column by an operand, row by row. The operand is either a literal number or, with the $n syntax, the value of another column of the same row. Literal divisors handle unit conversion (100-nanosecond intervals to seconds with value: 10000000, milliseconds to seconds with value: 1000); $n divisors compute ratios such as usage / capacity for a utilization metric. The column values must be numeric, and the divisor must not be 0.

Syntax

sources:
  processInformation:
    type: wmi
    namespace: root\CIMv2
    query: SELECT Name,ProcessId,KernelModeTime,UserModeTime FROM Win32_Process
    computes:
    # Convert 100-nanosecond intervals to seconds
    - type: divide
      column: 3
      value: 10000000

Properties

Table Transformation Example

With column: 3 and value: 10000000, column 3 of each row is divided by 10,000,000:

Recommended Pattern

• Comment both the source unit and the target unit next to the compute (# unit = 100-nanosecond intervals, # divide by 10000000 to get seconds).
• For utilization metrics, duplicate the usage column first (duplicateColumn), then divide the copy by the capacity column with value: $n — keeping the raw usage for the usage metric.
• Chain one divide per column when the same divisor applies to several columns of the row.

Common Mistakes

• Dividing by 0, either literally or through a $n reference to a column that can hold 0 or an empty value.
• Reversing the operands: divide computes column / value, never value / column.
• Converting units twice: check whether the mapping already applies a conversion function before also dividing in the compute pipeline.
• Pointing column or $n at indexes that were shifted by an earlier compute such as keepColumns or awk.

Community Examples

• Windows^[1]
• WindowsProcess^[2]
• Cassandra^[3]

From Windows.yaml, computing memory utilization ratios against the total held in column 7, included directly from the connector source:

# Calculate utilization by dividing usage by total memory
- type: divide
  column: 2
  value: $7
- type: divide
  column: 4
  value: $7
- type: divide
  column: 6
  value: $7