Diluted earning per share

Dividends are paid from Retained earnings. That does not impact EPS. 

There are many ways DPS is calculated, one is for issuing additional shares. If you issue additional shares, DPS changes.

Another instance where dividends is used is when convertible preference shares are exercised with cumulative dividend, and it is antidilutive. Meaning, EPS will increase and loss will decrease.

Dilutive EPS means EPS will decrease, loss will increase. Your first part is correct. DPS need not be calculated not unless the following happens:

Options & Warrants

Rights issue for employee

Additional issue

Convertible preference shares

In your second part, dividends are subtracted from net profit to get the numerator. 

**I meant while paying dividends, EPS is used for dividend decisions sometimes, but the procedure is different. I also meant it impacts EPS, typo error

You can’t calculate dps when there are no additional issue. Yes subtract it.