Difference between revisions of "User:Regina"
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=== FISHER and FISHERINV=== | === FISHER and FISHERINV=== | ||
| − | Reduced accuracy for r->0 | + | Reduced accuracy for r -> 0 |
| − | Needs log1p for improvement | + | Needs log1p for improvement. |
1/2*log((1+r)/(1-r)) = 1/2*log(1+2*r/(1-r)) = 1/2* log1p(2r/(1-p)) | 1/2*log((1+r)/(1-r)) = 1/2*log(1+2*r/(1-r)) = 1/2* log1p(2r/(1-p)) | ||
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1/2*(log(1+r)-log(1-r)) = 1/2*( log1p(r)-log1p(-r)) | 1/2*(log(1+r)-log(1-r)) = 1/2*( log1p(r)-log1p(-r)) | ||
| − | Have to test | + | Have to test it. |
| + | :Test done. Accuracy is the same. But all have additional problem for r -> 1. Seems to be the known problem with 1-r. | ||
| − | + | Achtung: Fisher(r) = arctanh(r). Letztere hat das gleiche Problem für r -> 0. | |
| − | (exp(2r)-1)/(exp(2r)+1) | + | Same problem in FISHERINV with (exp(2r)-1)/(exp(2r)+1) |
| + | |||
| + | Achtung FISHERINV(r)=tanh(r) | ||
| + | : tanh ist compiler core function in math.h | ||
== Sandbox == | == Sandbox == | ||
Revision as of 23:12, 10 December 2008
- native language
- German
- active in project
- de, qa. sc
- OOo user name
- regina
- special interest
- www.ooowiki.de
Contents
ToDo
Working on functions sides
Functions listed alphabetically, Functions listed by category
Planning Wiki-Pages
FISHER and FISHERINV
Reduced accuracy for r -> 0
Needs log1p for improvement.
1/2*log((1+r)/(1-r)) = 1/2*log(1+2*r/(1-r)) = 1/2* log1p(2r/(1-p))
or
1/2*(log(1+r)-log(1-r)) = 1/2*( log1p(r)-log1p(-r))
Have to test it.
- Test done. Accuracy is the same. But all have additional problem for r -> 1. Seems to be the known problem with 1-r.
Achtung: Fisher(r) = arctanh(r). Letztere hat das gleiche Problem für r -> 0.
Same problem in FISHERINV with (exp(2r)-1)/(exp(2r)+1)
Achtung FISHERINV(r)=tanh(r)
- tanh ist compiler core function in math.h
Sandbox
Test Wiki-markup here
