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update JoeKuoD6initializers

Open xuruilong100 opened this issue 4 years ago • 8 comments

In fact, JoeKuoD5initializers and JoeKuoD7initializers can contain 21200 direction numbers now, just as JoeKuoD6initializers. See https://web.maths.unsw.edu.au/~fkuo/sobol/

BTW,

  1. the comments (// maxTabulated=1799) for JoeKuoD6 is wrong, it should be // maxTabulated=21200.
  2. maybe, JoeKuoD6 is a better choice than Jaeckel as the default argument for SobolRsg.

xuruilong100 avatar Oct 27 '21 07:10 xuruilong100

It seems that, the direction numbers used by Sobol sequences in NAG, SciPy and Julia are same as JoeKuoD6initializers. So, JoeKuoD6 is a better choice.

See,

xuruilong100 avatar Oct 27 '21 08:10 xuruilong100

I agree to change the default — also, the D6 numbers should be updated since the version we have is pre-June 2010.

I'm not sure about extending D5 and D7; it adds a lot of size and they're probably unused.

lballabio avatar Oct 27 '21 09:10 lballabio

I agree to change the default — also, the D6 numbers should be updated since the version we have is pre-June 2010.

I'm not sure about extending D5 and D7; it adds a lot of size and they're probably unused.

JoeKuoD7 is used by SobolBrownianBridgeRsg as default argument.

xuruilong100 avatar Nov 08 '21 02:11 xuruilong100

JoeKuoD7 is used by SobolBrownianBridgeRsg as default argument.

Do you think we should move it to D6, too?

lballabio avatar Nov 08 '21 07:11 lballabio

Sorry, I don't know, it is beyond my knowledge. But professor Kuo says that D6 is the recommended choice.

xuruilong100 avatar Nov 09 '21 02:11 xuruilong100

Hmm, I gave it a try and moving to D6 as the default caused some figures in the tests to get worse. This might need some investigation.

lballabio avatar Nov 11 '21 13:11 lballabio

On the other hand, I stand corrected — we already have the correct post-2010 version of the D6 numbers.

lballabio avatar Nov 11 '21 13:11 lballabio