working with List of Maps

Question

Hi! 
 I'm having trouble trying to modify this list of maps (which I get from a!queryRecordType with an aggregation). 
 local!Grades: { a!map(Group: "A", Excellent: 0, Good: 0, Regular: 0), a!map(Group: "A", Excellent: 2, Good: 0, Regular: 0), a!map(Group: "B", Excellent: 0, Good: 0, Regular: 2), a!map(Group: "B", Excellent: 0, Good: 2, Regular: 0), a!map(Group: "C", Excellent: 0, Good: 2, Regular: 0), }, 
 The aggregation does not allow me to get each Group in only 1 row, because I need to "count" the grades by category (Excellent, Good, Regular) 
 I would like to display that result in a read-only grid and am trying to prepare the data before displaying it there (as I read in some other suggestions). 
 The result I am trying to obtain is this: 
 local!Grades: { a!map(Group: "A", Excellent: 2, Good: 0, Regular: 0), a!map(Group: "B", Excellent: 0, Good: 2, Regular: 2), a!map(Group: "C", Excellent: 0, Good: 2, Regular: 0), }, 
 In other words, I want to match each row of the grid to each group, and the columns will be: "Excellent", "Good", " Regular ". 
 I tried using 2 nested foreach... but it doesn't work. 
 Please, help me with some ideas! 
 Thank you in advance!

Mike Schmitt · Accepted Answer

It doesn't even really require a nested ForEach or (if you'd rather avoid the legacy function) reduce(), just a bit of reassembly using a!forEach(). 
 a!localVariables(
 local!Grades: {
 a!map(Group: "A", Excellent: 0, Good: 0, Regular: 0),
 a!map(Group: "A", Excellent: 2, Good: 0, Regular: 0),
 a!map(Group: "B", Excellent: 0, Good: 0, Regular: 2),
 a!map(Group: "B", Excellent: 0, Good: 2, Regular: 0),
 a!map(Group: "C", Excellent: 0, Good: 2, Regular: 0),
 },
 
 local!uniqueGroups: rule!RULE_General_distinct( 
 /* simple helper rule that unions an array against itself */
 value: local!Grades.Group
 ),
 
 a!forEach(
 local!uniqueGroups,
 
 a!localVariables(
 local!listForCurrentGroup: index(
 local!Grades,
 wherecontains(fv!item, local!Grades.Group),
 {}
 ),
 a!map(
 Group: fv!item,
 ExcellentSum: sum(local!listForCurrentGroup.Excellent),
 GoodSum: sum(local!listForCurrentGroup.Good),
 RegularSum: sum(local!listForCurrentGroup.Regular)
 )
 )
 )
)

working with List of Maps

Top Replies