[[NumPy]]で数値マトリクス以外の構造を扱う。 [Structured arrays — NumPy v1.22 Manual](https://numpy.org/doc/stable/user/basics.rec.html) from [python - Add string column to float matrix NumPy - Stack Overflow](https://stackoverflow.com/questions/53279442/add-string-column-to-float-matrix-numpy)