Log / Computation Layer

Calculate the logarithm with a specified base for each value in a numeric column. Similar to numpy.log(), pandas.eval('log()'), or R's log() function.

Mathematical form: where is the specified base and is the row index.

Common applications:

  • Scale compression (reducing data range)
  • Information theory (bits of information)
  • Sound intensity (decibel calculations)
  • pH calculations (hydrogen ion concentration)
  • Earthquake magnitude (Richter scale)
  • Network analysis (graph distances)
  • Psychological scaling (Weber-Fechner law)

Note: Input values must be positive. Negative or zero inputs result in null values.

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Transforms

[, ...]

Select

column

The numeric column to compute logarithms for. Values must be positive (> 0). Common input types:

  • Raw measurements (sound power, light intensity)
  • Counts or frequencies (occurrence data)
  • Ratios or proportions (concentration levels)
  • Scale values (energy measurements)

Base

f64
2.718281828459045

The logarithm base (Base). Common values:

  • e ≈ 2.71828 (natural logarithm, default)
  • 2 (binary logarithm, for computer science)
  • 10 (common logarithm, for engineering)
  • Other bases for specific applications

Must be positive and not equal to 1.

Name for the new column. If not provided, the system generates a unique name. If AsColumn matches an existing column, the existing column is replaced. The name should follow valid column naming conventions.