How do you compare the GDP growth rate and economic growth during NDA's and UPA's rule at the Centre (India)?

We cannot. Any two situations, where time paradigm is different, cannot be compared. Its very subjective and will never be an apple to apple situation. The closest one can get to compare two situations is by looking at few indicators like trade deficit, per capita income, INR-USD exchange rate, unemployment rate and a few more of such neutral indicators.

F*** the numbers, your question sprouts only three points in my mind: During NDA's rule, I could fill my car to its heart's content with petrol within Rs. 1,600 (35 litres).  Now I can do only half as much. If Goa (BJP-ruled) can offer petrol at Rs. 40 a litre by abolishing govt. levies on it (and improving trade/commerce as a result), I do hope that's the kind of productive subsidy Indians need. Not the doles given out in Robinhood style, knowing how funds are siphoned off in mafiosi ways via PDS. I wouldn't have had to answer this question as anonymous during NDA's rule.  UPA hounds even the mildest of dissent with secret police.

1)GDP is basically a number which is sum total of country's import and export of goods and services. This number varies with countries capacity to produce goods and services which is highly dependant on government policy formulations and its expenditure for development of economy. GDP is a process which shows hardly negative growth because with time countries power to produce goods and services increase if everything goes right. Some factors like FDI,  products on which we import have effect on GDP. So we can't compare GDP growth solely on the government which is ruling or was in rule. 2)Economic growth rate is another concept which is completely different from GDP. Factor like price index (WPI/CPI),  financial inclusion... etc taken into account to know the growth of economy and to calculate growth rate of economy by comparing it with previous years NDA government changed the basis to calculate it from WPI to CPI (consumer price index) so our growth rate shown very much increase than previous govt. So here to the possibility of comparison is grey.