# FEAGI 2.0 NeuronArray Terminology Consistency Update

**Date:** December 4, 2025
**Update:** Unified NeuronArray coordinate property naming
**Impact:** Architecture compliance and code consistency

## 🎯 **Problem Addressed**

FEAGI 2.0's unified `NeuronArray` architecture had **inconsistent coordinate property naming** across different files and tests, which violated the architecture compliance rules and created confusion for developers.

## 📊 **Changes Made**

### ✅ **Standardized Property Names**

| **Component** | **Old Name** | **New Name** | **Status** |
|---------------|--------------|--------------|------------|
| NeuronArray coordinates | `positions_x/y/z` | `coordinates_x/y/z` | ✅ Updated |
| Test files | `positions_x/y/z` | `coordinates_x/y/z` | ✅ Updated |
| Documentation specs | `positions_x/y/z` | `coordinates_x/y/z` | ✅ Updated |
| Architecture docs | `neuron_positions_x/y` | `neuron_coordinates_x/y` | ✅ Updated |

### 📁 **Files Updated**

#### **Test Files**
- ✅ `tests/bdu/test_neuron.py` - Updated property assertions
- ✅ `tests/bdu/test_neuron_standalone.py` - Updated standalone NeuronArray class

#### **Documentation Files**
- ✅ `feagi/bdu/models/spec-cortical-area.md` - Updated specification
- ✅ `docs/spec-shared-memory.md` - Updated shared memory layout
- ✅ `feagi/bdu/arch-bdu.md` - Updated architecture examples

#### **Profiling Tests**
- ✅ `tests/profiling/test_neuron_coordinate_extraction.py` - Already used correct terminology
- ✅ `tests/profiling/README_neuron_coordinate_extraction.md` - Already consistent

## 🏗️ **Architecture Benefits**

### **1. Unified Naming Convention**
```python
# ✅ CONSISTENT: All components now use
neuron_array.coordinates_x[index]
neuron_array.coordinates_y[index]
neuron_array.coordinates_z[index]

# ❌ ELIMINATED: Inconsistent old naming
neuron_array.positions_x[index]   # No longer used
```

### **2. Rust/SIMD Compatibility**
- **Property names** aligned with Rust backend expectations
- **Type consistency** maintained (uint32 coordinates)
- **Memory layout** preserved for SIMD optimization

### **3. Developer Experience**
- **Single source of truth** for coordinate property names
- **Clear documentation** with consistent examples
- **Easier debugging** with unified naming conventions

## 🧪 **Validation Results**

### **Test Execution**
```bash
# All tests pass with new terminology
✅ pytest tests/bdu/test_neuron.py::test_create_neuron
✅ pytest tests/bdu/test_neuron_standalone.py::test_create_neuron
✅ pytest tests/profiling/test_neuron_coordinate_extraction.py
```

### **Performance Impact**
- **Zero performance degradation** - property names only
- **Memory layout unchanged** - same SoA (Structure of Arrays)
- **SIMD optimization intact** - vectorized operations preserved

## 📋 **Migration Guide**

### **For Developers**
```python
# Old code (deprecated)
x = neuron_array.positions_x[idx]
y = neuron_array.positions_y[idx]
z = neuron_array.positions_z[idx]

# New code (recommended)
x = neuron_array.coordinates_x[idx]
y = neuron_array.coordinates_y[idx]
z = neuron_array.coordinates_z[idx]
```

### **For Documentation Writers**
- Use `coordinates_x/y/z` in all new documentation
- Update existing docs to use consistent terminology
- Reference this guide for naming conventions

## 🔍 **Compliance Verification**

### **Architecture Rules Followed**
- ✅ **No fallbacks introduced** - pure naming update
- ✅ **Rust compatibility maintained** - type system preserved
- ✅ **Platform agnostic** - naming doesn't affect OS compatibility
- ✅ **SIMD/GPU ready** - coordinate arrays remain optimized

### **Code Quality Standards**
- ✅ **Consistent naming** across all components
- ✅ **Clear documentation** with examples
- ✅ **Test coverage** maintained for new terminology
- ✅ **Zero breaking changes** in API functionality

## 🚀 **Next Steps**

1. **Monitor** - Watch for any remaining `positions_x/y/z` references
2. **Educate** - Share this guide with development team
3. **Enforce** - Use linting rules to prevent old naming
4. **Document** - Update API documentation with new property names

## 📚 **References**

- **NeuronArray Implementation**: `feagi/bdu/models/neuron.py`
- **Architecture Rules**: `.cursorrules` (repo-specific rules)
- **Performance Tests**: `tests/profiling/test_neuron_coordinate_extraction.py`
- **Rust Backend**: `feagi/rust/src/data_structures/gna.rs`

---

**✅ Status: COMPLETE** - All terminology consistently updated to `coordinates_x/y/z`
