Example with a dynamic dimension = 1

_doc/index.rst

@@ -71,11 +71,17 @@ Enlightening Examples
 
 * :ref:`l-plot-export_tiny_phi2`
 
-**Torch Export**
+**Exporter Recipes**
 
+* :ref:`l-plot-export-dim1`
 * :ref:`l-plot-export-cond`
 * :ref:`l-plot-export-with-dynamic`
 * :ref:`l-plot-export-with-dynamic-shape`
+* :ref:`l-plot-dynamic-shapes-python-int`
+
+**Torch Export Models**
+
+* :ref:`l-plot-nonzero`
 * :ref:`l-plot-export-locale-issue`
 * :ref:`l-plot-tiny-llm-export`
 * :ref:`l-plot-tiny-llm-export-patched`

_doc/recipes/plot_dynamic_shapes_nonzero.py

@@ -1,4 +1,6 @@
 """
+.. _l-plot-nonzero:
+
 Half certain nonzero
 ====================
 

_doc/recipes/plot_export_dim1.py

@@ -0,0 +1,64 @@
+"""
+.. _l-plot-export-dim1:
+
+0, 1, 2 for a Dynamic Dimension in the dummy example to export a model
+======================================================================
+
+:func:`torch.export.export` does not work if a tensor given to the function
+has 0 or 1 for dimension declared as dynamic dimension.
+
+Simple model, no dimension with 0 or 1
+++++++++++++++++++++++++++++++++++++++
+"""
+
+import torch
+from onnx_diagnostic import doc
+
+
+class Model(torch.nn.Module):
+    def forward(self, x, y, z):
+        return torch.cat((x, y), axis=1) + z
+
+
+model = Model()
+x = torch.randn(2, 3)
+y = torch.randn(2, 5)
+z = torch.randn(2, 8)
+model(x, y, z)
+
+DYN = torch.export.Dim.DYNAMIC
+ds = {0: DYN, 1: DYN}
+
+ep = torch.export.export(model, (x, y, z), dynamic_shapes=(ds, ds, ds))
+print(ep.graph)
+
+# %%
+# Same model, a dynamic dimension = 1
+# +++++++++++++++++++++++++++++++++++
+
+z = z[:1]
+
+DYN = torch.export.Dim.DYNAMIC
+ds = {0: DYN, 1: DYN}
+
+try:
+    ep = torch.export.export(model, (x, y, z), dynamic_shapes=(ds, ds, ds))
+    print(ep.graph)
+except Exception as e:
+    print("ERROR", e)
+
+# %%
+# It failed. Let's try a little trick.
+
+# %%
+# Same model, a dynamic dimension = 1 and backed_size_oblivious=True
+# ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+
+with torch.fx.experimental._config.patch(backed_size_oblivious=True):
+    ep = torch.export.export(model, (x, y, z), dynamic_shapes=(ds, ds, ds))
+    print(ep.graph)
+
+# %%
+# It worked.
+
+doc.plot_legend("dynamic dimension\nworking with\n0 or 1", "torch.export.export", "green")