WolframLang: Association, Delete by Key

Delete by Key, Modify Variable

KeyDropFrom[assocVar, key]

remove the element with the specified key. KeyDropFrom

xx = Association[ a -> 1, b -> 2];
KeyDropFrom[ xx, b ] === <|a -> 1|>

KeyDropFrom[assocVar, {key1, key2 etc}]

remove multiple elements

xx = Association[ a -> 1, b -> 2, c -> 3, d -> 4];
KeyDropFrom[ xx, {a, c} ] === <|b -> 2, d -> 4|>

Delete by Key, No Modify Variable

KeyDrop

return a new association with some keys removed. (does not modify variable) KeyDrop

xx = Association[ a -> 1, b -> 2, c -> 3 ];
KeyDropFrom[ xx, b ] === <|a -> 1, c -> 3|>