Documentation/Calc Functions/GAMMADIST

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Function name:

GAMMADIST

Category:

Statistical Analysis

Summary:

Calculates the value of the probability density function or the cumulative distribution function for the gamma distribution.

Im-jabber.svg

Note:
The inverse function for GAMMADIST is GAMMAINV or GAMMA.INV.

Syntax:

GAMMADIST(Number; Alpha; Beta[; C])

Returns:

Returns a real number which is a value of the probability density function or the cumulative distribution function for the Gamma distribution. Its value ranges from 0 to 1, i.e. [0,1].

Arguments:

Number is a real number or a reference to the cell containing that number for which the gamma distribution is to be calculated.

Alpha is a real number or a reference to the cell containing that number which is the alpha (shape) parameter for the gamma distribution.

Beta is a real number or a reference to the cell containing that number which is the beta (rate) parameter for the gamma distribution.

C can be 0 or False to calculate the probability density function. It can be any other value or True to calculate the cumulative distribution function. By default, its value is 0.

  • If either of Alpha or Beta is negative or zero then the function returns an error value.
  • If Number is negative then the function returns an error value.

Additional details:

  • The formula for GAMMADIST is:

If C is FALSE(), GAMMADIST returns 0 if x=0, an error value if x<0 and the probability density function value

Gammadistc.png

If C is TRUE(), GAMMADIST returns 0 if x=0, an error value if x<0 and the cumulative distribution function value

Gammadistp.png
  • For more details on gamma distribution, visit Wikipedia.

Examples:

Formula Description Returns
=GAMMADIST(4,3.4,4.5,0) The function calculates the probability density function for the gamma distribution with Number as 4, Alpha as 3.4 and Beta as 4.5 . 0.023098822632503
=GAMMADIST(4,3.4,4.5,1) The function calculates the cumulative distribution function for the gamma distribution with Number as 4, Alpha as 3.4 and Beta as 4.5 . 0.033711040932054
=GAMMADIST(0,3.4,4.5,1) The function returns 0 for Number equal to 0, given all arguments are valid. 0
=GAMMADIST(-4,3.4,4.5,1) The Number is negative hence the function returns an error value. Err:502

Related LibreOffice functions:

GAMMA.INV

GAMMA.DIST

GAMMAINV

ODF standard:

Section 6.18.31, part 2

Equivalent Excel functions:

GAMMADIST