Collabora Office BETADIST: Beta CDF, density and scaled bounds
Use legacy BETADIST with its sixth-position cumulative flag, scaled support and out-of-range behavior in the pinned Linux desktop source.
Verification status: See the evidence and test scope described in this guide. How formula examples are checked
Quick answer: =BETADIST(0.5;2;3) independently gives 0.6875, the left cumulative probability for a beta distribution with shapes 2 and 3. To request density instead, supply both bounds before the sixth-position flag: =BETADIST(0.5;2;3;0;1;FALSE()) gives 1.5.
A density can exceed 1. It is not the probability that a continuous random variable equals the exact input value; interval probabilities come from integrating density or subtracting CDF values.
Syntax and defaults
=BETADIST(Number; Alpha; Beta [; Start [; End [; Cumulative]]])
Alpha and Beta are positive shape parameters. Start defaults to 0, End to 1, and Cumulative to TRUE. End must be strictly greater than Start. The final flag is FALSE/0 for density and TRUE/nonzero for cumulative probability. Official BETADIST help.
Supply explicit Start and End when setting the sixth argument. Do not move Cumulative into position four: that is the separate dotted BETA.DIST contract. With =BETADIST(0.5;2;3;0), the zero is a lower bound and the function still defaults to cumulative mode.
The standardized coordinate is z=(Number−Start)/(End−Start). The CDF is the unit-interval beta CDF at z. Density additionally divides by the interval width, so its units are inverse units of Number.
Worked example: shapes 2 and 3
In a fresh sheet enter B2 = 0.5, B3 = 2 and B4 = 3. Use =BETADIST(B2;B3;B4) for the CDF, and =BETADIST(B2;B3;B4;0;1;FALSE()) for density.
For these shapes, the density is 12z(1−z)^2, and the CDF is 6z^2−8z^3+3z^4. At z = 0.5:
- CDF =
1.5−1+0.1875= 0.6875. - Density =
12×0.5×0.25= 1.5.
These polynomial calculations independently reproduce the expected function values. They do not rely on execution of the vendor engine. The CDF means 68.75% of the model’s mass lies at or below 0.5, while the density describes the local probability concentration.
Advanced use: a bounded quantity from 10 to 20
Keep the same shapes but let the modeled quantity range from 10 to 20. For Number = 15, z is still 0.5:
| Formula | Independent result |
|---|---|
=BETADIST(15;2;3;10;20) |
0.6875 |
=BETADIST(15;2;3;10;20;FALSE()) |
0.15 |
The CDF is unchanged by the coordinate transformation. Density is divided by 10, the width of the new interval. Treating density as a probability would miss this essential scaling difference.
For the probability between 14 and 17, use:
=BETADIST(17;2;3;10;20)-BETADIST(14;2;3;10;20)
The standardized endpoints are 0.4 and 0.7. Their CDF values are 0.5248 and 0.9163, so the interval probability is 0.3915. The shapes are assumed model inputs; this formula does not estimate them or validate whether a beta model fits the observations.
Domain behavior and singular endpoints
The legacy ScBetaDist evaluator returns CDF 0 below Start and 1 above End. Its density is 0 strictly outside the support. Thus =BETADIST(-1;2;3) predicts 0 and =BETADIST(2;2;3) predicts 1. These legacy boundary extensions differ from the dotted evaluator’s out-of-range rejection.
Nonpositive shapes and nonpositive interval width follow internal IllegalArgument; for example, equal bounds 1 and 1 are invalid. At a support endpoint, densities can be finite, zero or singular depending on the shapes. The density helper signals an internal error for the divergent lower endpoint when Alpha < 1, and analogously for the upper endpoint when Beta < 1. Do not interpret a failure at a singular endpoint as zero probability over a nearby interval.
Native error localization, extreme-parameter accuracy and formatting have not been tested. Use explicit numerical bounds and inspect the requested mode before interpreting a result.
Product scope, compatibility and evidence
This guide covers the new Collabora Office desktop for Linux, using the Flathub source tag coda-26.04.4.3-1 and commit 81339d176148d0d5c81ff05d82540f58f8aaa117. The official desktop release notes and Linux package manifest identify that product/build. The package manifest is a dated observation from October 18, 2026, rather than an installed-binary check.
The 26.04 function help and exact evaluator source were inspected on October 18, 2026. Expected examples were independently calculated; no Collabora application was run. Expected scalar results were derived from the documented contracts, inspected source and independent calculations; native output formatting and error localization have not been tested. Classic, Online/CODE, other operating systems and file-format round trips require their own checks.
These are the documented legacy contracts. A similar dotted name does not establish identical argument order, defaults or boundary behavior. The first Collabora release introducing this function is not established by the reviewed sources. No cited retirement or deprecation notice was found; “legacy” here describes the function contract, not a claim that the function has been removed. File-format round trips require separate verification.