fix(scoring): extract LaTeX a\times10^{b} as one scientific term

pyproject.toml

@@ -18,7 +18,7 @@ dependencies = [
 ]
 
 [project.optional-dependencies]
-dev = ["pytest>=8.0", "ruff>=0.5", "mypy>=1.10"]
+dev = ["pytest>=8.0", "ruff>=0.5,<0.16", "mypy>=1.10"]
 
 [build-system]
 requires = ["hatchling"]

src/trinity/adapters/drop.py

@@ -130,9 +130,12 @@ def _maybe_unbox(segment: str) -> str:
     return boxed if boxed is not None else ""
 
 
-#: Surrounding punctuation stripped from a token, EXCLUDING the signs ``+``/``-`` — a
-#: leading sign is part of a number's value, not wrapping noise.
-_STRIP_EDGE = "".join(c for c in string.punctuation if c not in "+-")
+#: Surrounding punctuation stripped from a token, EXCLUDING the signs ``+``/``-`` and
+#: the decimal point ``.`` — a leading sign or decimal point is part of a number's
+#: value, not wrapping noise. A genuinely-trailing ``.`` (sentence period) is handled
+#: by the dedicated rstrip retry in :func:`_normalize_token`, which can tell it apart
+#: from a value-bearing leading point; a blanket edge-strip cannot.
+_STRIP_EDGE = "".join(c for c in string.punctuation if c not in "+-.")
 
 
 def _normalize_token(raw: str) -> str:
@@ -147,20 +150,27 @@ def _normalize_token(raw: str) -> str:
     dropped the ``-`` and left commas to break ``float()``) did not deliver.
 
     A token that is ALREADY a number is recognised before any punctuation is
-    stripped: the edge-strip set includes ``.``, so a leading-decimal token like
-    ``".5"`` would otherwise lose its point and normalize to ``"5.0"`` — equal to
-    a gold ``"5"`` (false positive) and unequal to the value-identical gold
-    ``"0.5"`` (false negative). The official DROP ``_remove_punc`` tests
-    ``_is_number`` first and leaves numbers untouched for exactly this reason."""
+    stripped: a leading-decimal token like ``".5"`` must not lose its point and
+    normalize to ``"5.0"`` — equal to a gold ``"5"`` (false positive) and unequal
+    to the value-identical gold ``"0.5"`` (false negative). The official DROP
+    ``_remove_punc`` tests ``_is_number`` first and leaves numbers untouched for
+    exactly this reason (issue #423). The float-first path alone only covers the
+    *bare* token: with ``.`` in the edge-strip set, wrapped forms like ``"$.5"``
+    and ``".5."`` still lost the leading point on the second-chance path. So the
+    edge strip excludes ``.`` entirely, and a genuinely-trailing period (``".5."``,
+    ``"16.."``) is retried with an explicit ``rstrip(".")`` — right-side dots are
+    sentence punctuation, left-side dots are value."""
     try:
         return str(float(raw.replace(",", "")))
     except ValueError:
         pass
     core = raw.strip(_STRIP_EDGE)
-    try:
-        return str(float(core.replace(",", "")))
-    except ValueError:
-        return _PUNCT.sub("", raw)
+    for cand in (core, core.rstrip(".")):
+        try:
+            return str(float(cand.replace(",", "")))
+        except ValueError:
+            continue
+    return _PUNCT.sub("", raw)
 
 
 def _split_internal_hyphens(token: str) -> list[str]:

src/trinity/orchestration/reward.py

@@ -514,14 +514,19 @@ def extract_last_number(text: str) -> str | None:
         r"|-?\d+\s*/\s*-?\d+"
         # Scientific notation BEFORE bare decimals so "1e3" is not read as "3".
         r"|-?(?:\d+(?:\.\d+)?|\.\d+)[eE][+-]?\d+"
+        # LaTeX scientific ``a\times 10^{b}`` BEFORE bare digits so the exponent
+        # is not taken alone (issue #485). Sibling of the ``1e3`` form above.
+        rf"|-?(?:\d+(?:\.\d+)?|\.\d+)\s*\\times\s*10\s*\^(?:{brace}|[+-]?\d+)"
         r"|-?(?:\d{1,3}(?:,\d{3})+|\d+)(?:\.\d+)?"
         r"|-?\.\d+"
     )
     for m in pattern.finditer(text):
         candidates.append((m.end(), m.group(0).replace(",", "").replace(" ", "")))
     if not candidates:
         return None
-    candidates.sort(key=lambda item: item[0])
+    # Latest end wins; on a tie prefer the longer span so ``3\times 10^{2}`` beats
+    # the trailing exponent digit that ends at the same index (issue #485).
+    candidates.sort(key=lambda item: (item[0], len(item[1])))
     return candidates[-1][1]
 
 

tests/test_reward_times_ten_scientific.py

@@ -0,0 +1,24 @@
+"""Unboxed ``a\\times 10^{b}`` must not grade as the exponent digit (issue #485)."""
+
+from trinity.orchestration.reward import extract_last_number, score_text
+
+
+def test_extract_times_ten_as_whole_term():
+    # Spaces inside the match are stripped (same as other extract candidates).
+    assert extract_last_number(r"3\times 10^{2}") == r"3\times10^{2}"
+    assert extract_last_number(r"answer is $3\times 10^{2}$") == r"3\times10^{2}"
+    assert extract_last_number(r"2.5\times 10^3") == r"2.5\times10^3"
+
+
+def test_unboxed_times_ten_grades_value_not_exponent():
+    assert score_text("math500", r"the answer is $3\times 10^{2}$", "300") == 1.0
+    assert score_text("math500", r"the answer is $3\times 10^{2}$", "2") == 0.0
+
+
+def test_boxed_times_ten_still_works():
+    assert score_text("math500", r"\boxed{3\times 10^{2}}", "300") == 1.0
+
+
+def test_ascii_scientific_still_works():
+    assert extract_last_number("the answer is 1e3") == "1e3"
+    assert score_text("math500", "the answer is 1e3", "1000") == 1.0