RectangularRepeatingElement
RectangularRepeatingElement[elem] represents a rectangular array of elements of type spec in an interpreter, API or form specification.
RectangularRepeatingElement[elem,{maxrows,maxcolumns}] represents a rectangular array of elements of maximum size maxrows×maxcolums.
RectangularRepeatingElement[elem,{{minrows,maxrows},{mincolumns,maxcolumns}}] represents a rectangular array of elements of dimensions between minrows×mincolumns and maxrows×maxcolums.
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