Statistical Operation¶
Computes a single statistical measure from a comma-separated list of numeric values. Supports mean, median, mode, standard deviation, variance, sum, product, and count. The node parses the input string into numbers and returns the requested statistic as a float, applying population formulas for variance and standard deviation.
Usage¶
Use this node when you need to derive a summary statistic from a list of values for downstream logic or parameterization. Typical workflows include aggregating scores, normalizing decisions based on data distribution, or counting items from a numeric list provided by earlier nodes.
Inputs¶
| Field | Required | Type | Description | Example |
|---|---|---|---|---|
| values | True | STRING | Comma-separated list of numbers to analyze. Spaces are allowed and ignored around numbers. Non-numeric entries will cause the node to return 0.0. | 1, 2, 3, 4, 5 |
| operation | True | CHOICE | The statistical operation to compute. One of: mean, median, mode, std, variance, sum, product, count. | mean |
Outputs¶
| Field | Type | Description | Example |
|---|---|---|---|
| result | FLOAT | The computed statistic from the input list. Uses population formulas for variance and standard deviation; mode returns the most frequent value. | 3.0 |
Important Notes¶
- Input format: Provide values as a comma-separated STRING (e.g., "1,2,3"). Any non-numeric token results in a 0.0 output.
- Empty or invalid input: If parsing yields no valid numbers, the node returns 0.0.
- Population metrics: std and variance are computed using population formulas (divide by N), not sample (N-1).
- Mode ties: If multiple values are equally frequent, the first most-common value encountered is returned.
- Output type: The result is returned as a FLOAT, even for operations like count.
- Product initialization: Product starts at 1 and multiplies across all numbers.
Troubleshooting¶
- Got 0.0 unexpectedly: Ensure all entries in 'values' are valid numbers separated by commas; remove stray characters or empty entries.
- Incorrect std/variance expectation: This node uses population formulas. If you expected sample statistics, adjust accordingly (e.g., compute variance * N/(N-1)).
- Mode seems ambiguous: With multiple modes, the node returns the first most frequent value; pre-filter or deduplicate if a specific tie-breaking is required.
- Precision issues: Floating-point rounding can affect mean, std, and variance; limit value magnitudes or round downstream if necessary.