3 + Fast and easy calculation for large numerical array.
5 8,16,32 bit integer, single/double float/complex, Ruby Object.
6 + Easy extraction/substitution of array subset,
7 using assignment with number, range, array index.
8 + Operator: +,-,*,/,%,**, etc.
9 + FFTW version 2 or 3 is separately supported.
10 + NImage: Image viewer class.
11 + Ruby/PGPLOT: Graphics library interface (separately distributed)
12 X-Y Graph, Histogram, Contour map, Image map, etc.
14 * NArray is similar to:
16 + Python/NumPy, Perl/PDL, Yorick, IDL