[daip] DFTPL

[Farhad Zadeh]

Hi Eric,

I knew something was wrong when I include  multiple IFs.

Glad you fixed it. I think it used to work.

Thanks,

Farhad


On 3/1/17 10:50 AM, Eric Greisen wrote:
> On 02/13/2017 02:38 PM, Farhad Zadeh wrote:
>> Hi Eric,
>>
>> I have a big data set with 64 IFs and 64 channels over 8 GHz at Ka band.
>> I have done DFTPL for individual
>>
>> IFs and it works fine as it should. The mean flux changes because of
>> frequency dependence of the Sgr A*.  However, when I use all
>>
>> IFs, I dont see a range of flux expected between  the low and high
>> frequencies. It does averaging  but not all light curves are included.
>>
>> I think this used to work. Am I doing something wrong?
>>
>> Thanks,
>>
>> Farhad
>>
>> PS I which we could have waterfall presentation of light curves for
>> different frequencies in DFTPL.
>
>
> I found a serious error in DFTPL - it effectively ignores all IFs > BIF
> or at least 3/4 of the data since it strides through the data 4 times 
> faster than it should.  This has now been fixed in 31DEC16 and 31DEC17.
>
> I also write a new task DFTIM in 31DEC17 only which makes the 
> waterfall image you requested (and an optional error image).  The X 
> axis is spectral channel (and you can average channels within IFs) and 
> the Y axis is time with the same time averaging as DFTPL.
>
> I cleaned up some things in both - you cannot do cross-hands RL and LR 
> since they are not Hermitian which DFTPL and DFTIM assume. So I added 
> STOKES and ignore BPARM(1).  This lets you do I, Q, U, V with RR/LL 
> data sets which I think was forbidden before.
>
> Enjoy
>
> Eric
>