Difference between revisions of "User:Regina"
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Revision as of 16:21, 5 October 2008
- native language
- German
- active in project
- de, qa. sc
- OOo user name
- regina
- special interest
- www.ooowiki.de
Sandbox
CHISQDIST
Calculates values for a χ2-distribution.
Syntax
CHISQDIST(x; k; Cumulative)
- x is the number, at which you will evaluate the χ2-distribution.
- k sets the degrees of freedom for the χ2-distribution
- Constraint: k must be a positive integer
- Cumulative is a logical value.
- In the case Cumulative=TRUE() the cumulative distribution function is used, in the case Cumulative=FALSE() the probability density function. This parameter is optional. It is set to TRUE() if missing.
Semantic
CHISQDIST(x;k;FALSE()) returns values of the probability density function for the χ2-distribution:
CHISQDIST(x;k;TRUE()) returns the left tail probability for the χ2-distribution:
Example
CHSQDIST(2.7;3;FALSE())
- returns approximately 0.1699395239
CHSQDIST(2.7;3;TRUE())
- returns approximately 0.5597727056
Remarks
If you need CHISQDIST(x;k;TRUE()) with a non integer parameter k, then use GAMMADIST(x;k/2;2) instead.
In the density case the internal calculation uses logarithmic- and exponential function, if x >1425 or x · k > 1391000. Therefore it is less accurate then than in other cases.
See also:
CHISQINV, LEGACY.CHIDIST, LEGACY.CHIINV, CHITEST
Functions listed alphabetically, Functions listed by category
Issues:
This function is expected for OOo3.1
CHISQINV
Calculates the inverse of the CHISQDIST function.
Syntax
CHISQINV(p; k)
- k is the degrees of freedom for the χ2-distribution.
- Constraint: k must be a positive integer
- p is the given probability
- Constraint: 0 ≤ p < 1
Semantic
- CHISQINV(p; k) returns the value x, such that CHISQDIST(x; k;TRUE()) = p.
Example
CHISQINV(0.5; 9)
- returns approximately 8.342832692
.
Remarks
If you need CHISQINV(p;k) for a non interger parameter k, then use GAMMAINV(p;k/2;2) instead.
See also:
Functions listed alphabetically, Functions listed by category
Issues:
- This function is expected for OOo3.1
GAMMA
Returns the values of the Gamma function.
Syntax
GAMMA(x)
- x is a number.
- Constraint: If x is an integer, then x must be positive.
Semantic
GAMMA(x) calculates
- .
Example
- GAMMA(4) = 6.0 exact
- GAMMA(34.56) ≈ 6.2336323276E+037
- GAMMA(−4) not defined
Remarks
For x < 0.5 Eulers reflection formula is used.
The Gamma function has poles for negative integers and for zero. Near the poles the values are less accurate.
If x is a positive integer, then
But be aware, that OpenOffice.org has only a precision of 15 digits, therefore the results for x > 21 are rounded.
See also:
GAMMALN, GAMMADIST, GAMMAINV, FACT
Functions listed alphabetically, Functions listed by category
Issues:
This function is expected for OOo3.1.