Follow-up to #10287, which added `max`. Expressing a minimum still
required spelling out `(a + b - |a - b|) / 2`, the sign flip of the max
identity — drop the `neg` and you silently get a maximum instead. It also
only works for two operands and mentions each one twice, so the scorer
walks every sub-tree twice per candidate point.
The pair is what makes clamping expressible:
{"max": [0.0, {"min": [1.0, "$score"]}]}
`min` mirrors `max` throughout, and both guard helpers introduced in
#10287 already took an `operator: &str`, so they are reused unchanged: an
empty operand list is rejected at parse time rather than folding to
+infinity, and the Edge FFI rejects it at construction time. The result
needs no `is_finite` check, since `min` cannot produce a non-finite value
from finite inputs.
The unindexed-field walker shares one arm for `Max | Min` as the bodies
are identical, with a test pinning `min` separately so a later split
cannot silently drop it.
Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
* feat: add a dedicated max operator to score formulas
Expressing a maximum in a score formula required spelling out the
arithmetic identity `(a + b + |a - b|) / 2`. That is easy to get wrong
(the `/ 2` is load-bearing), only works for two operands, and mentions
each operand twice, so the scorer evaluates every sub-tree twice per
candidate point.
`max` is variadic, mirroring `sum` and `mult`:
{"max": ["$score", {"mult": [0.5, "popularity"]}]}
Unlike `sum` and `mult`, `max` has no identity element for the empty
case, so an empty operand list is rejected at parse time rather than
folding to -infinity and scoring every point with a non-finite value.
The check lives in `ExpressionInternal::parse_and_convert`, which every
entry point passes through, and the Edge FFI additionally rejects it at
construction time to match how that crate validates elsewhere.
The result needs no `is_finite` check: unlike `log10`, `exp`, `div`,
`sqrt` and `pow`, `max` cannot produce a non-finite value from finite
inputs, so it follows the existing `sum` convention.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
* test: cover max error propagation and datetime operands
An operand that fails must fail the whole expression rather than being
passed over in favour of a finite sibling. Covered with the failure both
before and after the finite operand: `mult` short-circuits on zero and
so can skip evaluating later operands, and this pins down that `max`
must not grow a similar shortcut that would swallow an error.
Also covers `max` over datetime operands, which reach the scorer through
a separate conversion to seconds, so that "score by whichever timestamp
is newer" is verified rather than assumed.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
---------
Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
Unary inverse hyperbolic cosine, parallel to sqrt/ln/exp/log10, in REST,
gRPC, and edge (FFI + Python) interfaces. Inputs below 1 produce the same
NonFiniteNumber error as an invalid sqrt or ln.
Closes#10186
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
* handle `score_threshold` in Formula queries
* AI: add openapi test
prompt: Upload 4 points with a numeric payload, use the payload as the
score, and set a score threshold. We can assert which ids should be in
the result and which shouldn't
