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--- extract_lookup_table_attributes [2016/04/24 05:06]
hermann [Statistical Value Attributes]
+++ extract_lookup_table_attributes [2026/08/28 03:18] (current)
hermann Sync from local documentation review
@@ Line 1: / Line 1: @@
 ====== Extract Lookup Table Attributes ======
 ===== Description =====
-This functor extracts attributes and summary statistics from a lookup table.
+Extracts general attributes and basic statistics from a lookup table, returning them as a lookup table keyed by a predefined attribute code.
 ===== Inputs =====
 ^ Name  ^ Type  ^ Description  ^
-| Table  | [[Lookup Table Type]]  |  A lookup table.  |
+| Table  | [[Lookup Table Type]]  | Lookup table whose attributes will be extracted.  |
 ===== Optional Inputs =====
 ^ Name  ^ Type  ^ Description  ^ Default Value  ^
-| Extract Statistical Key Attributes  | [[Boolean Value Type]]  | If true, the calculation includes statistical key attributes (items 10-16). | True  |
+| Extract Statistical Key Attributes  | [[Boolean Value Type]]  | If true, statistical key attributes (items 10-16) are also extracted.  | True  |
-| Extract Statistical Value Attributes  | [[Boolean Value Type]]  | If true, the calculation includes statistical value attributes (items 20-26). | False  |
+| Extract Statistical Value Attributes  | [[Boolean Value Type]]  | If true, statistical value attributes (items 20-26) are also extracted.  | True  |
-| Extract Dynamic Key Value Attributes  | [[Boolean Value Type]]  | If true, the calculation includes statistical value attributes (items 30-32). | False  |
+| Extract Dynamic Key Value Attributes  | [[Boolean Value Type]]  | If true, dynamic key and value attributes (items 30-32) are also extracted.  | True  |
 ===== Outputs =====
 ^ Name  ^ Type  ^ Description  ^
-|  Attributes  | [[Lookup Table Type]]  | Table containing the attributes extracted from a table.  |
+| Attributes  | [[Lookup Table Type]]  | Table of extracted attributes, keyed by attribute code.  |
 ===== Group =====
-[[Functor List#Table | Table]]
+[[Functor List#Lookup Table | Lookup Table]]
 ===== Notes =====
-The functor employs a lookup table with keys to the attributes. Each key has a predefined name. This name can be used to retrieve the corresponding attribute in [[Calculate Map]], [[Calculate Categorical Map]], [[Calculate Value]] and [[Calculate Lookup Table]]
+Each attribute has a predefined name that can be used to retrieve it by name (rather than by numeric key) with the ''tX["NAME"]'' syntax in [[Calculate Map]], [[Calculate Categorical Map]], [[Calculate Value]], and the lookup table calculators.
-==== Basic Attributes ====
+If an attribute cannot be determined, its entry is omitted from Attributes rather than being filled with a placeholder.
-^ Key ^ Predefined Name ^ Description                   ^
+Static attributes and their keys: 1 "uniqueKeys" (number of unique keys, i.e. rows).
-| 1   | "uniqueKeys"    | number of unique keys (lines) |
-==== Statistical Key Attributes ====
+Statistical key attributes and their keys (present only when Extract Statistical Key Attributes is true), where each key's associated value is used as that key's number of occurrences: 10 "minKey", 11 "maxKey", 12 "meanKey", 13 "modeKey", 14 "keyVar", 15 "keyStd", 16 "medianKey". Keys associated with a negative or zero value are treated as absent from the table for this calculation. To instead treat every key as occurring exactly once regardless of its associated value, first pass Table through a [[Calculate Lookup Table Values]] with the expression ''1'' to turn every value into 1, and extract attributes from the result.
-The value mapped to the key by each key/value pair is used as the number of key occurrences.
+Statistical value attributes and their keys (present only when Extract Statistical Value Attributes is true): 20 "minValue", 21 "maxValue", 22 "meanValue", 23 "modeValue", 24 "valueVar", 25 "valueStd", 26 "medianValue".
-^ Key ^ Predefined Name ^ Description            ^
+Dynamic key and value attributes and their keys (present only when Extract Dynamic Key Value Attributes is true): 30 "keySum" (sum of the keys; associated values are ignored), 31 "valueSum" (sum of the values), 32 "keyValueProdSum" (sum of each key multiplied by its associated value).
-| 10  | "minKey"        | minimum key            |
-| 11  | "maxKey"        | maximum key            |
-| 12  | "meanKey"       | mean key               |
-| 13  | "modeKey"       | mode key               |
-| 14  | "keyVar"        | key variance           |
-| 15  | "keyStd"        | key standard deviation |
-| 16  | "medianKey"     | median key             |
-==== Statistical Value Attributes ====
+The minimum and maximum key or value attributes are only determined when Table has at least one entry.
-^ Key ^ Predefined Name ^ Description                ^
+===== Internal Name =====
-| 20  | "minValue"        | minimum value            |
-| 21  | "maxValue"        | maximum value            |
-| 22  | "meanValue"       | mean value               |
-| 23  | "modeValue"       | mode value               |
-| 24  | "valueVar"        | value variance           |
-| 25  | "valueStd"        | value standard deviation |
-| 26  | "medianValue"     | median value             |
-==== Dynamic Key & Value Attributes ====
-^ Key ^ Predefined Name   ^ Description                  ^
-| 30  | "keySum"          | key sum (values are ignored) |
-| 31  | "valueSum"        | value sum                    |
-| 32  | "keyValueProdSum" | sum of key/value product     |
-If it is not possible to determine any of those attributes, the corresponding entry in the lookup table is left blank.
-===== Internal Name =====
 ExtractLookupTableAttributes