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Hello

The concept of set is almost the first thing taught in mathematics, for this reason, I think you should add a submenu in [TOOLS] [Math] [Set] with the following eight instructions, with symbols as tags

1:∪
2: ∩
3: \
4: ×
5: ∈
6: ⊂
7: Δ
8: '

1: ∪
example set[ "b", "a", "c", "a" ] union set[ "a", "d" ] //[↵] set["b","a","c","d"]

2: ∩
set[ "b", "a", "c", "a" ] intersect set[ "a", "d" ] //[[↵] set["a"]

3: \ (minus)
set[ "b", "a", "c", "a" ] minus set[ "a", "d" ] //[[↵] set["b","c"]

4: × (cartesian product)
set[ "b", "a", "c", "a" ] * set[ "a", "d" ] //[ [↵]

[["b","a"],
["b","d"],
["a","a"],
["a","d"],
["c","a"],
["c","d"]]

5: ∈ (is_element)
evalb(is_element("a",set["b","a","c","a"])) [↵]true // For a more intuitive output the numeric value [>0]/0 should be symbolix true/false, in this way the use of the EVALB() command is avoided.

6: ⊂ (is_included) this function is not yet visible in the hp-prime catalog =(

evalb(is_included(set[ "a", "d" ], set[ "b", "a", "c", "a" ])) [↵] false

7: Δ (Symmetric difference )

M_:= set[ "A", "B", "C"];
N_:= set[ "B", "G", "L", "E"];
U_:= set[ "A", "B", "C", "G", "L", "E", "I", "J", "F", "H"]

M_ union N_ //[[↵] set["A","B","C","G","L","E"]
M_ intersect N_ //[[↵] set["B"]
M_ minus N_ //[[↵] set["A","C"]
M_ Δ N_ //[[↵] set["G","L","E","A","C"] // Code:
8: ' (Complement )
M' U //[[↵] set["G","L","E","I","J","F","H"] // Code: U_ minus M_
N' U //[[↵] set["A","C","I","J","F","H"] // Code: U_ minus N_

This is awesome. Great suggestion compsystems!

It would be interesting a separate application for this task, I think it would be colorful

I notice that in the LIST menu, it has three set commands, but the list type is not always equal to a set

test

index:=1:; E_ := [ "H", "E", "L", "L", "O" ]:;
find( "L", E_ ) [enter]
[3,4] // "L" is in two positions
index(E_,"L") [enter]
3

F_ := set[ "H", "E", "L", "L", "O" ] [enter] set[ "H", "E", "L", "O" ]
find( "L", F_ ) [enter]
[3] // "L" is in one positions
index(F_,"L") [enter]
3

E_ == F_ [enter] false

also diference cmd does not work on a set
DIFFERENCE(set["b","a","c","a"],set["a","d"]) [enter]
{"b","c","d"}

set[ "b", "a", "c", "a" ] minus set[ "a", "d" ] [↵] set["b","c"]