Questions on dying black hair?

So next week I am putting a few streaks (or panels) of purple in my black long and curly hair (vanessa hudgens style) but I am still a little worried about what shade of purple. i LOVE the purple with katy perrys hair in "Firework" music video. But for black hair what shade should i go? (plum, darker purple, brighter purple, bluish purple, redish purple, etc)