Differences

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--- 15_cheatsheet:operators [2025/11/03 04:24] – created gaetan
+++ 15_cheatsheet:operators [2026/04/21 14:28] (current) – [Selection Operators] Tim
@@ Line 1: / Line 1: @@
 ====== XL operators ======
-XL-Operators are designed to simplify the usage of XL queries and rewriting rules. Moreover these operators can improve the performance of a query due to there deep integration into the model.
+XL-Operators are designed to simplify the usage of XL queries and rewriting rules. Moreover these operators can improve the performance of a query due to their deep integration into the model.
-In the following the operators a separated into Analytical and selection operators to either get a value for analysis or a node/ a collection of nodes for rewriting.
+In the following, the operators a separated into analytical and selection operators to either get a value for analysis or a node/ a collection of nodes for rewriting.
 ====== Analytical Operators ======
@@ Line 16: / Line 16: @@
 | forall((*//query//*)[//value//]//condition//) | checks if a condition is true for the all results of the query |forall((*f:F*)[length]==1) |
 | exist((*//query//*)[//value//]//condition//) | checks if a condition is true for at least one result of the query |exist((*f:F*)[length]==1) |
+|statistics((*//query//*)[//value//] |return an instance of the class [[https://javadoc.grogra.de/rgg/de/grogra/rgg/Statistics.html| Statistics]] |statistics((*F*)[length]) |
@@ Line 24: / Line 25: @@
 | first((*//query//*) ) | get the first element found with the query | first((*F*) ) |
 | last((*//query//*) ) | get the last element found with the query | last((*F*) ) |
-| slice((*//query//*),//s//,//e//) | return the subset(form s to e) of the result | slice((*F*),2,4), slice((*F*)[length],2,4)  |
+| slice((*//query//*),//s//,//e//) | return the subset(from s to e) of the result | slice((*F*),2,4), slice((*F*)[length],2,4)  |
 |selectWhere((*//query//*),//condition//)| Select a node of the query that fits the condition | selectWhere((*f:F*),f[length]==1) |
 |selectWhereMin((*//query//*),//parameter//)| Select a node of the query where the parameter is the smallest | selectWhereMin((*f:F*),f[length])  |
 |selectWhereMax((*//query//*),//parameter//)| Select a node of the query where the parameter is the largest | selectWhereMax((*f:F*),f[length]) |
 |selectRandomly((*//query//*) )| select a Random node from the query | selectRandomly((*F*) ) |
-|selectRandomly((*//query//*),prob)| ??? | ???  |
+|selectRandomly((*//query//*),prob)| select a Random node from the query using a given numeric value as weight | selectRandomly((*f:F*),f[length])  more likely to pick longer Fs |