Tighten rtol/atol from 1e-2 to 1e-3 for Helion kernels (#132)

All four Helion kernels (causal_conv1d, gated_deltanet_chunk_fwd_h,
chunk_fwd_o, recompute_w_u) operate in float32 but used overly loose
tolerances of rtol=1e-2, atol=1e-2. Tighten to 1e-3 to better catch
numerical bugs while still allowing for accumulation chain error.

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: yf225

problems/helion/causal_conv1d_py/reference.py

@@ -32,4 +32,4 @@ def ref_kernel(data: input_t) -> output_t:
         return output
 
 
-check_implementation = make_match_reference(ref_kernel, rtol=1e-2, atol=1e-2)
+check_implementation = make_match_reference(ref_kernel, rtol=1e-3, atol=1e-3)

problems/helion/gated_deltanet_chunk_fwd_h_py/reference.py

@@ -96,8 +96,8 @@ def check_implementation(data, output):
     exp_h, exp_v = expected
     got_h, got_v = output
 
-    reasons_h = verbose_allclose(got_h.float(), exp_h.float(), rtol=1e-2, atol=1e-2)
-    reasons_v = verbose_allclose(got_v.float(), exp_v.float(), rtol=1e-2, atol=1e-2)
+    reasons_h = verbose_allclose(got_h.float(), exp_h.float(), rtol=1e-3, atol=1e-3)
+    reasons_v = verbose_allclose(got_v.float(), exp_v.float(), rtol=1e-3, atol=1e-3)
 
     reasons = []
     if reasons_h:

problems/helion/gated_deltanet_chunk_fwd_o_py/reference.py

@@ -112,4 +112,4 @@ def ref_kernel(data: input_t) -> output_t:
     return o.permute(0, 1, 3, 2, 4).reshape(B, T, H, V).to(q.dtype)
 
 
-check_implementation = make_match_reference(ref_kernel, rtol=1e-2, atol=1e-2)
+check_implementation = make_match_reference(ref_kernel, rtol=1e-3, atol=1e-3)

problems/helion/gated_deltanet_recompute_w_u_py/reference.py

@@ -72,8 +72,8 @@ def check_implementation(data, output):
     exp_w, exp_u = expected
     got_w, got_u = output
 
-    reasons_w = verbose_allclose(got_w, exp_w, rtol=1e-2, atol=1e-2)
-    reasons_u = verbose_allclose(got_u, exp_u, rtol=1e-2, atol=1e-2)
+    reasons_w = verbose_allclose(got_w, exp_w, rtol=1e-3, atol=1e-3)
+    reasons_u = verbose_allclose(got_u, exp_u, rtol=1e-3, atol=1e-3)
 
     reasons = []
     if reasons_w: