Got to read this piece of news today. NRIs and foreigners are restricted from carrying Indian rupee outside India. They need to convert into other currencies like dollar or Euro before they step out of the country. Previously I guess, you can have at the max of 10,000 INR as cash amount in your hand while leaving India, but now you cannot.
Please click on this link --- Indian Economy News --- to learn more.
So, keep this in mind, before you step out of the country. Happy Flying.