Logarithmic Operation¶
Performs logarithmic and exponential calculations on a single numeric value. Supports custom-base logarithms, natural and common logs, and exponential functions with bases e and 2. Inputs are validated and the node returns 0.0 for invalid or out-of-domain values.
Usage¶
Use this node when you need to transform values using logarithms (e.g., compression, normalization, scale adjustments) or exponentials (e.g., growth modeling, re-scaling). Typical workflows include data preparation, numeric feature engineering, or mathematical pipelines where you must switch between log and exp domains.
Inputs¶
| Field | Required | Type | Description | Example |
|---|---|---|---|---|
| value | True | FLOAT | The primary input to operate on. For logarithms, this must be greater than 0. For exponentials, any float is allowed. | 100.0 |
| base | True | FLOAT | Base used only when operation is 'log' (custom-base logarithm). Must be > 0 and not equal to 1. Ignored for ln, log10, log2, exp, and exp2. | 10.0 |
| operation | True | ENUM | Select the operation to apply. Options: 'log' (custom base), 'ln' (natural log), 'log10' (base-10 log), 'log2' (base-2 log), 'exp' (e^value), 'exp2' (2^value). | log10 |
Outputs¶
| Field | Type | Description | Example |
|---|---|---|---|
| result | FLOAT | The computed numeric result of the selected operation, or 0.0 if inputs are invalid or out of domain. | 2.0 |
Important Notes¶
- Domain requirements: For logarithms, value must be > 0. For custom-base 'log', base must be > 0 and not equal to 1.
- Ignored base: The 'base' input is ignored for 'ln', 'log10', 'log2', 'exp', and 'exp2'.
- Safety behavior: If inputs are invalid (e.g., non-positive value for log), the node returns 0.0 and logs a warning.
- Precision and range: Extremely large inputs for exponential operations can overflow or produce very large results; the node will attempt the computation but may return 0.0 on error.
- Input constraints: UI limits typically constrain value and base to [0.001, 1e10] for safer interaction.
Troubleshooting¶
- Result is 0.0 unexpectedly: Check that 'value' > 0 for all logarithmic operations. For 'log' also ensure 'base' > 0 and not equal to 1.
- Base seems to have no effect: The 'base' input only affects the 'log' operation. It is not used for 'ln', 'log10', 'log2', 'exp', or 'exp2'.
- Overflow or extreme values: If using 'exp' or 'exp2' with large 'value', try reducing the magnitude or normalizing inputs to avoid overflow.
- Wrong operation selected: Verify the 'operation' choice matches your intent (e.g., use 'log10' for common log rather than 'log' with base 10 if you don't need a custom base).