From 286925fb83961c1cfee39e1804a045bd11180549 Mon Sep 17 00:00:00 2001
From: Ricardo Vieira <ricardo.vieira1994@gmail.com>
Date: Fri, 12 Jun 2026 16:42:27 +0200
Subject: [PATCH] Declare ndim_supp on value transforms

---
 pymc/distributions/transforms.py |  7 +++++++
 pymc/logprob/transforms.py       | 12 ++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/pymc/distributions/transforms.py b/pymc/distributions/transforms.py
index 4561152d50..b7e9a6718c 100644
--- a/pymc/distributions/transforms.py
+++ b/pymc/distributions/transforms.py
@@ -57,6 +57,7 @@ def _default_transform(op: Op, rv: TensorVariable):
 
 class LogExpM1(Transform):
     name = "log_exp_m1"
+    ndim_supp = 0
 
     def backward(self, value, *inputs):
         return pt.softplus(value)
@@ -84,6 +85,7 @@ class Ordered(Transform):
     """
 
     name = "ordered"
+    ndim_supp = 1
 
     def __init__(self, positive=False, ascending=True):
         self.positive = positive
@@ -124,6 +126,7 @@ class SumTo1(Transform):
     """
 
     name = "sumto1"
+    ndim_supp = 1
 
     def backward(self, value, *inputs):
         remaining = 1 - pt.sum(value[..., :], axis=-1, keepdims=True)
@@ -179,6 +182,7 @@ class CholeskyCorrTransform(Transform):
     """
 
     name = "cholesky_corr"
+    ndim_supp = 1
 
     def __init__(self, n, upper: bool = False):
         """
@@ -425,6 +429,7 @@ class CholeskyCovPacked(Transform):
     """Transforms the diagonal elements of the LKJCholeskyCov distribution to be on the log scale."""
 
     name = "cholesky-cov-packed"
+    ndim_supp = 1
 
     def __init__(self, n):
         """Create a CholeskyCovPack object.
@@ -494,6 +499,7 @@ class CholeskyCovTransform(Transform):
     """
 
     name = "cholesky-cov"
+    ndim_supp = 1
 
     def __init__(self, n):
         """Create a CholeskyCovTransform.
@@ -649,6 +655,7 @@ class ZeroSumTransform(Transform):
 
     def __init__(self, zerosum_axes):
         self.zerosum_axes = tuple(int(axis) for axis in zerosum_axes)
+        self.ndim_supp = len(self.zerosum_axes)
 
     @staticmethod
     def extend_axis(array, axis):
diff --git a/pymc/logprob/transforms.py b/pymc/logprob/transforms.py
index 3b551f6660..19c1e5bb12 100644
--- a/pymc/logprob/transforms.py
+++ b/pymc/logprob/transforms.py
@@ -744,6 +744,7 @@ def calc_delta_x(value, prior_result):
 
 class LocTransform(Transform):
     name = "loc"
+    ndim_supp = 0
 
     def __init__(self, transform_args_fn):
         self.transform_args_fn = transform_args_fn
@@ -762,6 +763,7 @@ def log_jac_det(self, value, *inputs):
 
 class ScaleTransform(Transform):
     name = "scale"
+    ndim_supp = 0
 
     def __init__(self, transform_args_fn):
         self.transform_args_fn = transform_args_fn
@@ -781,6 +783,7 @@ def log_jac_det(self, value, *inputs):
 
 class LogTransform(Transform):
     name = "log"
+    ndim_supp = 0
 
     def forward(self, value, *inputs):
         return pt.log(value)
@@ -794,6 +797,7 @@ def log_jac_det(self, value, *inputs):
 
 class ExpTransform(Transform):
     name = "exp"
+    ndim_supp = 0
 
     def forward(self, value, *inputs):
         return pt.exp(value)
@@ -807,6 +811,7 @@ def log_jac_det(self, value, *inputs):
 
 class AbsTransform(Transform):
     name = "abs"
+    ndim_supp = 0
 
     def forward(self, value, *inputs):
         return pt.abs(value)
@@ -821,6 +826,7 @@ def log_jac_det(self, value, *inputs):
 
 class PowerTransform(Transform):
     name = "power"
+    ndim_supp = 0
 
     def __init__(self, power=None):
         if not isinstance(power, int | float):
@@ -864,6 +870,7 @@ def log_jac_det(self, value, *inputs):
 
 class IntervalTransform(Transform):
     name = "interval"
+    ndim_supp = 0
 
     def __init__(self, args_fn: Callable[..., tuple[Variable | None, Variable | None]]):
         """Create the IntervalTransform object.
@@ -972,6 +979,7 @@ def log_jac_det(self, value, *inputs):
 
 class LogOddsTransform(Transform):
     name = "logodds"
+    ndim_supp = 0
 
     def backward(self, value, *inputs):
         return pt.expit(value)
@@ -986,6 +994,7 @@ def log_jac_det(self, value, *inputs):
 
 class SimplexTransform(Transform):
     name = "simplex"
+    ndim_supp = 1
 
     def forward(self, value, *inputs):
         value = pt.as_tensor(value)
@@ -1013,6 +1022,7 @@ def log_jac_det(self, value, *inputs):
 
 class CircularTransform(Transform):
     name = "circular"
+    ndim_supp = 0
 
     def backward(self, value, *inputs):
         return pt.arctan2(pt.sin(value), pt.cos(value))
@@ -1029,6 +1039,8 @@ class ChainedTransform(Transform):
 
     def __init__(self, transform_list):
         self.transform_list = transform_list
+        ndims_supp = [transform.ndim_supp for transform in transform_list]
+        self.ndim_supp = max(ndims_supp) if None not in ndims_supp else None
 
     def forward(self, value, *inputs):
         for transform in self.transform_list: