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Co-authored-by: jakirkham <jakirkham@gmail.com>

python/cucim/src/cucim/skimage/segmentation/_chan_vese.py

@@ -7,8 +7,6 @@
 from .._shared.utils import _supported_float_type
 from .._vendored import pad
 
-_one = cp.asarray(1.0, dtype=cp.float32)
-
 
 @cp.fuse()
 def _fused_variance_kernel1(eta, x_start, x_mid, x_end, y_start, y_mid, y_end):
@@ -55,7 +53,7 @@ def _fused_hphi_hinv(phi):
 
 @cp.fuse()
 def _fused_variance_kernel2(
-    image, c1, c2, lam1, lam2, phi, K, dt, mu, delta_phi, Csum, one
+    image, c1, c2, lam1, lam2, phi, K, dt, mu, delta_phi, Csum
 ):
     difference_term = image - c1
     difference_term *= difference_term
@@ -67,7 +65,9 @@ def _fused_variance_kernel2(
     difference_term += term2
 
     new_phi = phi + (dt * delta_phi) * (mu * K + difference_term)
-    out = new_phi / (one + mu * dt * delta_phi * Csum)
+    out_denom = mu * dt * delta_phi * Csum
+    out_denom += out_denom.dtype.type(1)
+    out = new_phi / out_denom
     return out
 
 
@@ -107,7 +107,7 @@ def _cv_calculate_variation(image, phi, mu, lambda1, lambda2, dt):
     c1, c2 = _cv_calculate_averages(image, Hphi, Hinv)
     delta_phi = _cv_delta(phi)
     out = _fused_variance_kernel2(
-        image, c1, c2, lambda1, lambda2, phi, K, dt, mu, delta_phi, Csum, _one
+        image, c1, c2, lambda1, lambda2, phi, K, dt, mu, delta_phi, Csum
     )
     return out