From ec2efe3246d1d3f4f5f53c5aeb5df8bb890079be Mon Sep 17 00:00:00 2001 From: Harrison Booth <73434116+Harrison-Booth@users.noreply.github.com> Date: Fri, 30 Oct 2026 19:34:36 -0500 Subject: [PATCH] G713: correct gamma density at zero --- crates/functions/src/stat/distributions.rs | 2 +- crates/functions/src/stat/tests.rs | 13 +++++++++++++ docs/function-parity.md | 3 ++- 3 files changed, 16 insertions(+), 2 deletions(-) diff --git a/crates/functions/src/stat/distributions.rs b/crates/functions/src/stat/distributions.rs index cb2f0398a..6f39f11a1 100644 --- a/crates/functions/src/stat/distributions.rs +++ b/crates/functions/src/stat/distributions.rs @@ -499,7 +499,7 @@ pub(super) fn gamma_dist(a: &[Arg], _: C) -> R { return if al < 1.0 { Err(CellError::Num) } else if al == 1.0 { - num_val(1.0 / be) + Err(CellError::Num) } else { num_val(0.0) }; diff --git a/crates/functions/src/stat/tests.rs b/crates/functions/src/stat/tests.rs index 87ce19fac..e45a48069 100644 --- a/crates/functions/src/stat/tests.rs +++ b/crates/functions/src/stat/tests.rs @@ -479,6 +479,19 @@ fn continuous() { close_tol(r[0][1].clone(), 0.841344746, 1e-8); } +#[test] +fn gamma_density_at_zero_shape_one_is_num() { + for scale in [0.1, 0.9, 1.0, 1.9, 2.0, 10_000_000_000.0] { + is_err(ev("GAMMA.DIST", vec![n(0.0), n(1.0), n(scale), b(false)]), CellError::Num); + } + is_err(ev("GAMMA.DIST", vec![n(0.0), n(0.5), n(1.0), b(false)]), CellError::Num); + close_tol(ev("GAMMA.DIST", vec![n(0.0), n(2.0), n(1.0), b(false)]), 0.0, 0.0); + close_tol(ev("GAMMA.DIST", vec![n(0.0), n(1.0), n(2.0), b(true)]), 0.0, 0.0); + close_tol(ev("GAMMA.DIST", vec![n(2.0), n(1.0), n(2.0), b(false)]), 0.5 * (-1.0f64).exp(), 1e-15); + close_tol(ev("GAMMA.DIST", vec![n(2.0), n(1.0), n(2.0), b(true)]), 1.0 - (-1.0f64).exp(), 1e-15); + is_err(ev("GAMMA.DIST", vec![n(-0.1), n(1.0), n(2.0), b(false)]), CellError::Num); +} + #[test] fn aggregate_helper() { let vals = vec![nv(1.0), nv(2.0), tv("x"), Value::Empty, Value::Bool(true), nv(6.0)]; diff --git a/docs/function-parity.md b/docs/function-parity.md index bf57fcd3e..6cfbd94a9 100644 --- a/docs/function-parity.md +++ b/docs/function-parity.md @@ -1,6 +1,6 @@ # Function parity: worksheet functions and formulas -> **Last reviewed:** 2026-10-15 · **Last updated:** 2026-10-25 · **Change:** minor (the LAMBDA row lists the recursion limit and its `#NUM!`, and the error a defined name holding an error gives when called; earlier: number text with accounting parentheses coerces like Excel 365; INDEX with one index on a 2-D reference is #REF! as in Excel; earlier: SUBTOTAL and AGGREGATE cap the cells they visit, #2175) · **Target:** Microsoft Excel (Microsoft 365), Excel for Mac 16.113.4 +> **Last reviewed:** 2026-10-31 · **Last updated:** 2026-10-31 · **Change:** minor (GAMMA.DIST density at x=0 and shape 1 returns `#NUM!` as in Excel; earlier: the LAMBDA row lists the recursion limit and its `#NUM!`, and the error a defined name holding an error gives when called; earlier: number text with accounting parentheses coerces like Excel 365; INDEX with one index on a 2-D reference is #REF! as in Excel; earlier: SUBTOTAL and AGGREGATE cap the cells they visit, #2175) · **Target:** Microsoft Excel (Microsoft 365), Excel for Mac 16.113.4 Excel's worksheet functions, category by category, against GridCraft's function library. Part of [target-app-parity.md](target-app-parity.md); gaps feed [gaps.md](gaps.md). @@ -123,6 +123,7 @@ workbooks; results checked in as data, not Excel files) and fixing what it finds | Date | Change | Summary | |---|---|---| +| 2026-10-31 | minor | GAMMA.DIST density at x=0 and shape 1 returns `#NUM!` for all positive scales; the cumulative branch and other shape boundaries are unchanged | | 2026-10-25 | minor | LAMBDA row: a LAMBDA that calls itself more than 140 times, and a formula nested past the depth limit, give `#NUM!` (#1809; nesting gave `#CALC!` before). `=Foo(1)` where the defined name Foo holds `#N/A` gives `#N/A`, not `#NAME?` | | 2026-10-23 | minor | Number text coercion (VALUE, arithmetic, typed entry): a dollar sign before accounting parentheses (`$(1,234)`, `$ (5)`) and a percent sign after them (`(5)%`) read as negatives; `(-5)`, `((5))`, `($-5)`, `$5%`, `$(5)%` and dates or times in parentheses are `#VALUE!`, as observed in Excel 365 | | 2026-10-23 | minor | INDEX with only a row index on a reference of several rows and columns (`INDEX(A1:C3,2)`, `INDEX(A1:C3,0)`) is `#REF!`, as observed in Excel, so it also fails as a range endpoint and inside other functions; an empty column argument (`INDEX(A1:C3,2,)`) still gives the row. Checked that a column array with one index stays a 1×1 array (`TYPE` 64), which is what Excel returns |