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 2021-09-14, 16:28 #100 Aillas     Oct 2002 France 15610 Posts EdH, I have a question about the source code: For open ended sequence, when looking for sequences that merge with Line 884: for(j=seqn+1;j 1000 that merge with prime related to sequence 1000. Or this is a bug and we should search the whole file? Thanks
2021-09-14, 20:18   #101
EdH

"Ed Hall"
Dec 2009

76418 Posts

Quote:
 Originally Posted by Aillas EdH, I have a question about the source code: For open ended sequence, when looking for sequences that merge with Line 884: for(j=seqn+1;j 1000 that merge with prime related to sequence 1000. Or this is a bug and we should search the whole file? Thanks
I hope I understand your question. The regina_file has already taken the first occurrance of an o-e sequence into account and the first one will count as number 1. All others will increment in the regina_file as more merges are encountered. Instead of using the regina_file count, seqinfo2 should simply start counting at seq+1 for any matches to seq. I think that's what I'm doing with that line.

Let me know If I'm still unclear or if I'm off on this.

Thanks for the question.

 2021-09-16, 11:32 #102 Aillas     Oct 2002 France 2348 Posts It's clear thanks. Bad news, I was updating the code to manage the perfect number, and there is a comparison with a prime number that could not fit in an uint64_t (seqd[seqn].elD == "191561942608236107294793378084303638130997321548169216") So I will try to update the code using double for this. This field is only used for comparison, so I don't think it will introduce issues. I need to try. I let you know.
 2021-09-16, 13:33 #103 EdH     "Ed Hall" Dec 2009 Adirondack Mtns 4,001 Posts Thanks for keeping us up-to-date on your work.
2021-09-22, 12:16   #104
Happy5214

"Alexander"
Nov 2008
The Alamo City

10111101102 Posts

Quote:
 Originally Posted by Aillas It's clear thanks. Bad news, I was updating the code to manage the perfect number, and there is a comparison with a prime number that could not fit in an uint64_t (seqd[seqn].elD == "191561942608236107294793378084303638130997321548169216") So I will try to update the code using double for this. This field is only used for comparison, so I don't think it will introduce issues. I need to try. I let you know.
I don't think a double (53-bit mantissa) is enough precision for that number, and even a long double on x86 (which I believe gives you the 80-bit x87 extended-precision float, with a 64-bit mantissa) isn't an improvement over uint64_t. I tried converting that number to float and back in Python (using double-precision) and it didn't return the same number:

Code:
>>> float(191561942608236107294793378084303638130997321548169216)
1.915619426082361e+53
>>> int(_)
191561942608236107294793378393788647952342390272950272
>>> _-191561942608236107294793378084303638130997321548169216
309485009821345068724781056

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