$ gem install narray (中略) Building native extensions. This could take a while... Successfully installed narray-0.6.1.2 [t]2017-05-02 22:10:46
NArray 新版
$ gem install numo-narray (中略) Building native extensions. This could take a while... Successfully installed numo-narray-0.9.0.6 [t]2017-05-02 22:15:14