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FilledSmallSquare AtomQ[expr] yields True if expr is an expression which cannot be divided into subexpressions, and yields False otherwise.

FilledSmallSquare You can use AtomQ in a recursive procedure to tell when you have reached the bottom of the tree corresponding to an expression.

FilledSmallSquare AtomQ gives True for symbols, numbers, strings and other raw objects, such as sparse arrays.

FilledSmallSquare AtomQ gives True on any object whose subparts cannot be accessed using functions like Map.

FilledSmallSquare See Section 2.3.5.

FilledSmallSquare See also: NumberQ, Head, LeafCount, Length.

FilledSmallSquare New in Version 1; modified in 5.0.

Further Examples