Compare commits

..
3 changed files with 25 additions and 46 deletions
+20 -2
View File
@@ -96,8 +96,11 @@ fn series_spans(data: &ChartData, fams: &[Fam], sec: &[bool], ncat: usize) -> Ve
} else {
None
};
let mut row = Vec::with_capacity(ncat);
for j in 0..ncat {
// A series without values has no spans: 255 empty series over 20,000 categories would
// otherwise fill ~5 million entries.
let n = if s.values.is_empty() { 0 } else { ncat };
let mut row = Vec::with_capacity(n);
for j in 0..n {
let v = s.values.get(j).copied().flatten();
let span = match (si.and_then(|p| stacks.get_mut(p)), fam) {
(Some((_, pos, neg)), Fam::ColStack | Fam::Col100) => v.and_then(|v| {
@@ -450,3 +453,18 @@ pub(super) fn scatter(ctx: &mut Ctx, chart: &Chart, data: &ChartData, area: Bx)
}
draw_trend_labels(ctx, plot, &trend_labels);
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn empty_series_get_no_span_entries() {
let empty = SeriesData::default();
let full = SeriesData { values: vec![Some(1.0); 3], ..SeriesData::default() };
let data = ChartData { series: vec![empty.clone(), full, empty], ..ChartData::default() };
let fams = [Fam::Col; 3];
let spans = series_spans(&data, &fams, &[false; 3], MAX_CATS);
assert_eq!(spans.iter().map(Vec::len).collect::<Vec<_>>(), [0, MAX_CATS, 0]);
}
}
+5 -24
View File
@@ -50,27 +50,12 @@ pub(super) fn median(v: Vec<f64>) -> R<f64> {
/// Values occurring at least twice, ordered by first occurrence, with their (equal, maximal) count.
fn modes(v: &[f64]) -> Vec<f64> {
// Index of each distinct number in `counts`, so counting is linear rather than a search of
// every distinct number so far. Keyed by bits with -0 folded into 0 (they compare equal); NaN
// never equals anything, so it is never merged.
let mut index: std::collections::HashMap<u64, usize> = std::collections::HashMap::new();
let mut counts: Vec<(f64, usize)> = Vec::new();
for &x in v {
if x.is_nan() {
if let Some(e) = counts.iter_mut().find(|e| e.0 == x) {
e.1 += 1;
} else {
counts.push((x, 1));
continue;
}
let key = if x == 0.0 { 0 } else { x.to_bits() };
match index.entry(key) {
std::collections::hash_map::Entry::Occupied(e) => {
if let Some(c) = counts.get_mut(*e.get()) {
c.1 += 1;
}
}
std::collections::hash_map::Entry::Vacant(e) => {
e.insert(counts.len());
counts.push((x, 1));
}
}
}
let best = counts.iter().map(|e| e.1).max().unwrap_or(0);
@@ -466,15 +451,11 @@ pub(super) fn frequency(a: &[Arg], _: C) -> R<Value> {
if bins.is_empty() {
return col_value(vec![data.len() as f64]);
}
// a NaN bin equals no value (and would break the ascending order searched below)
let mut order: Vec<usize> = (0..bins.len()).filter(|&i| bins.get(i).is_some_and(|b| !b.is_nan())).collect();
let mut order: Vec<usize> = (0..bins.len()).collect();
order.sort_by(|&i, &j| bins.get(i).copied().unwrap_or(0.0).total_cmp(&bins.get(j).copied().unwrap_or(0.0)));
let mut counts = vec![0.0; bins.len() + 1];
for x in data {
// `order` sorts the bins ascending, so the bins `x` exceeds come first: binary search for
// the first bin at or above `x` (the first of equal bins, as a linear scan would find).
let pos = if x.is_nan() { order.len() } else { order.partition_point(|&i| bins.get(i).copied().unwrap_or(f64::INFINITY) < x) };
let slot = order.get(pos).copied().unwrap_or(bins.len());
let slot = order.iter().find(|&&i| x <= bins.get(i).copied().unwrap_or(f64::INFINITY)).copied().unwrap_or(bins.len());
if let Some(c) = counts.get_mut(slot) {
*c += 1.0;
}
-20
View File
@@ -617,23 +617,3 @@ fn aggregate_helper() {
close(aggregate_values_k(9, &vals, &nv(2.0)), 9.0);
is_err(aggregate_values_k(14, &vals, &nv(10.0)), CellError::Num);
}
/// Security: FREQUENCY finds each value's bin by binary search, and MODE counts distinct numbers
/// through an index, so neither is quadratic in its inputs. Results are as before: unsorted and
/// duplicate bins keep their positions (a value goes to the first of equal bins), and tied modes
/// come in first-occurrence order.
#[test]
fn frequency_and_mode_scale_with_their_inputs() {
let f = ev("FREQUENCY", vec![c(&[1.0, 2.0, 2.0, 3.0, 5.0, 9.0, -1.0]), c(&[3.0, 2.0, 2.0, 0.0])]);
assert_eq!(rows_of(&f), vec![vec![nv(1.0)], vec![nv(3.0)], vec![nv(0.0)], vec![nv(1.0)], vec![nv(2.0)]]);
// NaN data goes to the overflow bin, and a NaN bin takes nothing
let f = ev("FREQUENCY", vec![c(&[f64::NAN, 0.5, 2.0]), c(&[f64::NAN, 1.0])]);
assert_eq!(rows_of(&f), vec![vec![nv(0.0)], vec![nv(1.0)], vec![nv(2.0)]]);
let data: Vec<f64> = (0..200_000).map(|i| f64::from(i) + 1e6).collect();
let bins: Vec<f64> = (0..200_000).map(f64::from).collect();
let f = ev("FREQUENCY", vec![c(&data), c(&bins)]);
assert_eq!(rows_of(&f).last(), Some(&vec![nv(200_000.0)]));
let distinct = ev("MODE", vec![c(&data)]);
is_err(distinct, CellError::NA);
assert_eq!(rows_of(&ev("MODE.MULT", vec![c(&[3.0, 0.0, 1.0, -0.0, 3.0, 1.0])])), vec![vec![nv(3.0)], vec![nv(0.0)], vec![nv(1.0)]]);
}