[Bioc-devel] FCS3.0 DiVa files?

Florian Hahne f.hahne at dkfz-heidelberg.de
Wed Sep 6 11:03:05 CEST 2006


Hi Byron,
do you think you could send me one of the diva files for testing
purposes. I like to test against as many different file types as
possible whenever I do changes to the import function and my supply is
somehow limited to FACS Array and FACS Calibur files. By the way, FSC
and SSC (and sometimes also other parameters) are viewed linearly
because the amplification of the measured signals by the instrument is
either linear or logarithmic, this can be set by the user. You can get
the type of amplification for each parameter n from the $PnE keyword in
the FCS file.
Cheers,
Florian

Byron Ellis schrieb:
> Actually, I stand corrected---I was looking at untransformed data and
> comparing to transformed data (the Forward Scatter is usually viewed
> linearly for whatever reason so it looked as it should). It looks like
> the SVN version (as of today) reads the FACSDiVa files correctly.
> Hooray. For the longest time it looked like there was an alignment
> problem or something, but apparently not.
>
> Of course there are negative entries for values that are,
> theoretically, photon counts but that's more the fault of the
> equipment manufacturers who thought that hardware background
> correction was a good idea. :-)
>
> P.S. Turning off a dump of the data matrix by default was a fantastic
> idea. My test data is 13x~520K  and that just kills Aqua R.
>
> On 9/5/06, Wolfgang Huber <huber at ebi.ac.uk> wrote:
>>
>> Hi Byron,
>>
>> would it be possible to be more specific than "weird sorts of systematic
>> errors", and for instance give some example files together with what you
>> consider correct results?
>>
>>    Best wishes
>>    Wolfgang
>>
>>
>>
>> Byron Ellis wrote:
>> > The latest readFCS unfortunately doesn't produce sensible results
>> > except for the first parameter (generally forward scatter), the other
>> > parameters have weird sorts of systematic errors that almost look like
>> > alignment problems. At least two other people in my lab here have Java
>> > importers for these sorts of files that I'm considering to be
>> > "correct" and working from there.
>> >
>> > On 9/4/06, Florian Hahne <f.hahne at dkfz-heidelberg.de> wrote:
>> >> Hi Byron,
>> >> As far as I know these files don't seem to adhere to the
>> specifications
>> >> in the FCS 3.0 format. I had one example file which I read in using a
>> >> number of different software tools and almost all of them produced
>> >> different results.
>> >> readFCS could read the file without errors and the plots of the data
>> >> looked ok. The only problem is that the absolute values are not
>> the same
>> >> for the different software, but the measurement relations are the
>> same,
>> >> i.e. the data is on different scales. And since I don't know what the
>> >> correct values are (and are there "correct" values at all? In the end
>> >> these are just arbitrary dimensionless numbers that somehow
>> reflect the
>> >> fluorescence intensities...) I didn't know how to proceed.
>> >> Please feel free to take a stab at the import if you think that is a
>> >> problem or send me one or two of your files along with some info
>> about
>> >> the expected range so I can give it another try.
>> >> Cheers,
>> >> Florian
>> >>
>> >> Byron Ellis schrieb:
>> >>> Hi all,
>> >>>
>> >>> I remember a couple of months ago there was a brief discussion about
>> >>> FCS3.0 files, in particular DiVA files recorded in floating
>> point. Was
>> >>> there ever any progress made on reading those in? I took a look
>> >>> through the logs, but I may have missed something. I suddenly find
>> >>> myself working with an LSR2 using DiVa that generates a lot of these
>> >>> files. :-)
>> >>>
>> >>> If not, I'll take a stab at it since I need to read these files
>> sooner
>> >>> rather than later.
>> >>>
>> >>>
>> >>
>> >> --
>> >> Florian Hahne
>> >> Abt. Molekulare Genomanalyse (B050)
>> >> Deutsches Krebsforschungszentrum (DKFZ)
>> >> Im Neuenheimer Feld 580
>> >> D-69120 Heidelberg
>> >> phone: 0049 6221 424764
>> >> fax: 0049 6221 423454
>> >> web: www.dkfz.de/mga
>> >>
>> >>
>> >
>> >
>>
>>
>
>


-- 
Florian Hahne
Abt. Molekulare Genomanalyse (B050)
Deutsches Krebsforschungszentrum (DKFZ)
Im Neuenheimer Feld 580
D-69120 Heidelberg
phone: 0049 6221 424764
fax: 0049 6221 423454
web: www.dkfz.de/mga



More information about the Bioc-devel mailing list