update hilbert2 to match scipy version 1.17

Author: takenori-y

Makefile

@@ -85,8 +85,8 @@ tool-clean:
 
 update: tool
 	. .venv/bin/activate && python -m pip install --upgrade pip
-	@for package in $$(./tools/taplo/taplo get -f pyproject.toml project.optional-dependencies.dev); do \
-		. .venv/bin/activate && python -m pip install --upgrade $$package; \
+	@./tools/taplo/taplo get -f pyproject.toml project.optional-dependencies.dev | while read -r package; do \
+		. .venv/bin/activate && python -m pip install --upgrade "$$package"; \
 	done
 
 clean: dist-clean doc-clean test-clean tool-clean

diffsptk/modules/hilbert2.py

@@ -112,13 +112,19 @@ def _precompute(
         TwoDimensionalHilbertTransform._check(dim)
         if isinstance(fft_length, int):
             fft_length = (fft_length, fft_length)
-        _, _, h1 = HilbertTransform._precompute(
-            fft_length[0], None, device=device, dtype=torch.double
-        )
-        _, _, h2 = HilbertTransform._precompute(
-            fft_length[1], None, device=device, dtype=torch.double
-        )
-        h = h1[0].unsqueeze(1) * h2[0].unsqueeze(0)
+
+        def get_weights(n: int) -> torch.Tensor:
+            _, _, h = HilbertTransform._precompute(
+                n, None, device=device, dtype=torch.double
+            )
+            h = h[0]
+            if 2 <= n:
+                h[(n + 1) // 2] = 0
+            return h
+
+        h1 = get_weights(fft_length[0])
+        h2 = get_weights(fft_length[1])
+        h = h1.unsqueeze(1) * h2.unsqueeze(0)
         return (dim,), None, (to(h, dtype=dtype),)
 
     @staticmethod

pyproject.toml

@@ -49,6 +49,7 @@ dev = [
   "pytest",
   "pytest-cov",
   "ruff",
+  "scipy >= 1.17.0",
   "sphinx",
   "twine",
 ]