[bug] Fix misbehaviour and assertion error on ti.math.sign

taichi-dev · May 26, 2023 · 5c77628 · 5c77628
1 parent d56f7b1
commit 5c77628
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Showing 2 changed files with 12 additions and 1 deletion.
diff --git a/python/taichi/math/mathimpl.py b/python/taichi/math/mathimpl.py
@@ -273,7 +273,7 @@ def sign(x):
         >>> ti.math.sign(x)
         [-1.000000, 0.000000, 1.000000]
     """
-    return ops.cast((x >= 0.0) - (x <= 0.0), float)
+    return ops.cast((x >= 0.0), float) - ops.cast((x <= 0.0), float)
 
 
 @func

diff --git a/tests/python/test_unary_ops.py b/tests/python/test_unary_ops.py
@@ -142,3 +142,14 @@ def test_u32(x: ti.uint32) -> ti.int32:
     assert test_u32(100) == 3
     assert test_u32(1000) == 6
     assert test_u32(10000) == 5
+
+
+@test_utils.test()
+def test_sign():
+    @ti.kernel
+    def foo(val: ti.f32) -> ti.f32:
+        return ti.math.sign(val)
+
+    assert foo(0.5) == 1.0
+    assert foo(-0.5) == -1.0
+    assert foo(0.0) == 0.0