On Mon, Jun 2, 2014 at 9:30 AM, Alexander Belopolsky <ndarray@mac.com> wrote:
It seems that there is not a percentile function for masked array in numpy or scipy?

Percentile is not  the only function missing in ma.   See for example

It seems to me that ma was treated on par with np.matrix in the recent years while several attempts were made to replace it with something better.

I don't think any better alternative have materialized, so it is probably time to declare that ma in the supported mechanism to deal with missing values in numpy and make an effort to keep the np and ma interfaces in sync. 

Masked arrays have no maintainer, and haven't for several years, nor do I see anyone coming along to take it up. It would be good to have methods for dealing with missing values in mainline as they would get more maintenance. Perhaps it is time to reopen that discussion and find a way forward.