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111 changes: 19 additions & 92 deletions README.md
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@@ -1,116 +1,43 @@
# ShearNet
# Dev Notes

A JAX-based neural network implementation for galaxy shear estimation.
## My Model vs Main Branch Model

## Installation
I tweaked the model at [this link](https://github.com/s-Sayan/ShearNet/blob/main/shearnet/core/models.py#L43) based of numerous research papers. The model I refer to is [here](./shearnet/core/models.py#L323). Plotted here is the comparison of the original model vs my new model.

### Quick Install
### Low Noise (nse_sd = 1e-5)

```bash
git clone https://github.com/s-Sayan/ShearNet.git
cd ShearNet
The comparison is also housed at [this directory](./notebooks/research_vs_control_low_noise/).

# CPU version
make install
Here is the comparions plots:

# GPU version (CUDA 12)
make install-gpu
![learning curve](./notebooks/research_vs_control_low_noise/learning_curves_comparison_20250702_172032.png)

# Activate environment
conda activate shearnet # or shearnet_gpu for GPU
```
### Manual Install
![residuals comparison](./notebooks/research_vs_control_low_noise/residuals_comparison_20250702_172126.png)

```bash
conda create -n shearnet python=3.11
conda activate shearnet
pip install -e .# or pip install -e ".[gpu]" for GPU
pip install git+https://github.com/esheldon/ngmix.git
python scripts/post_installation.py
```
![scatter comparison](./notebooks/research_vs_control_low_noise/prediction_comparison_20250702_172119.png)

## Usage
### High Noise (nse_sd = 1e-3)

### Train a model
The comparison is also housed at [this directory](./notebooks/research_vs_control_high_noise/).

```bash
shearnet-train --epochs 10 --batch_size 64 --samples 10000 --psf_sigma 0.25 --model_name cnn1 --plot --nn cnn --patience 20
```
or
```bash
shearnet-train --config ./configs/example.yaml
```
### Evaluate a model
Here is the comparions plots:

```bash
shearnet-eval --model_name cnn1 --test_samples 5000
```
Key options:
![learning curve](./notebooks/research_vs_control_high_noise/learning_curves_comparison_20250702_191955.png)

- `-nn`: Model type (`mlp`, `cnn`, or `resnet`)
- `-mcal`: Compare with metacalibration and NGmix
- `-plot`: Generate plots
![residuals comparison](./notebooks/research_vs_control_high_noise/prediction_comparison_20250702_192242.png)

## Example Results
![scatter comparison](./notebooks/research_vs_control_high_noise/residuals_comparison_20250702_192253.png)

ShearNet provides shear estimates for g1, g2, sigma, and flux parameters. Example performance on test data:
## Next Steps

### Comparison of predictions
<!-- <img src="./notebooks/scatter_plot_e1_scatter.png" alt="Comparison of Predictions" width="600"/> -->
My next steps are to impliment psf images into the training data. This will chage the initial shape from (batch_size, 53, 53) to (batch_size, 53, 53, 2). I hope to also get noise images eventually as well.

```
| Method | MSE (g1, g2) | Time |
|-----------------|--------------|-------|
| ShearNet | ~6e-4 | <1s |
| Moment-based | ~1e-2 | ~7s |
```

## Requirements

- Python 3.8+
- JAX (CPU/GPU)
- Flax, Optax
- GalSim, NGmix
- NumPy, SciPy, Matplotlib

See `pyproject.toml` for complete list.

## Repository Structure

```
ShearNet/
├── shearnet/
│ ├── core/ # Models, training, dataset
│ ├── methods/ # NGmix, moment-based
│ ├── utils/ # Metrics, plotting
│ └── cli/ # Command-line tools
├── scripts/ # Setup scripts
├── Makefile # Installation
└── pyproject.toml # Dependencies

```

## Python API

```python
from shearnet.core.dataset import generate_dataset
from shearnet.core.train import train_modelv2
import jax.random as random

# Generate data
images, labels = generate_dataset(10000, psf_fwhm=0.8)

# Train
rng_key = random.PRNGKey(42)
state, train_losses, val_losses = train_model(
images, labels, rng_key, epochs=50, nn='cnn'
)
```
Training on this should only increase the accuracy of ShearNet, and adding both psf and noise images will put it on even ground with NGMix.

## License

MIT License

## Contributing

Contributions welcome! Please submit issues or pull requests.
Contributions welcome! Please submit issues or pull requests.
8 changes: 4 additions & 4 deletions configs/example.yaml
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Expand Up @@ -3,12 +3,12 @@ dataset:
samples: 100000
psf_sigma: 0.25
exp: "ideal"
nse_sd: 1.0e-5
nse_sd: 1.0e-3
seed: 42

# Model configuration
model:
type: "cnn" # Options: mlp, cnn, resnet
type: "cnn" # Options: cnn, dev_cnn, resnet, dev_resnet

# Training configuration
training:
Expand All @@ -29,7 +29,7 @@ evaluation:
output:
save_path: null # Will use SHEARNET_DATA_PATH/model_checkpoint if null
plot_path: null # Will use SHEARNET_DATA_PATH/plots if null
model_name: "cnn1"
model_name: "control_cnn_high_noise"

# Plotting configuration
plotting:
Expand All @@ -40,4 +40,4 @@ comparison:
mcal: true
ngmix: true
psf_model: "gauss"
gal_model: "gauss"
gal_model: "gauss"
102 changes: 102 additions & 0 deletions configs/research_resnet.yaml
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# Research-Backed Training Configuration
# Every parameter choice justified by literature or empirical evidence

dataset:
# Citation: "Statistical Learning Theory" (Vapnik, 1998) - larger datasets improve generalization
# Practical: 100k samples provides sufficient statistical power for 4-parameter estimation
# Your Evidence: First successful model used similar scale effectively
samples: 100000

# Citation: "Euclid Survey" typical ground-based seeing conditions
# Astronomical Context: 0.25 arcsec ≈ 1.8 pixels at 0.141"/pixel scale
# Conservative Choice: Moderate PSF for stable performance baseline
psf_sigma: 0.25

# Experimental Control: Ideal conditions for baseline model development
# Future Work: Can extend to "superbit" for realistic conditions after validation
exp: "ideal"

# Citation: Signal-to-noise considerations for precision shape measurement
# Rationale: Low noise (1e-5) ensures algorithm performance dominates over measurement noise
# Comparable to space-based surveys like HST/JWST noise levels
nse_sd: 1.0e-3

# Reproducibility: Fixed seed for consistent train/val splits and initialization
seed: 42

model:
# Custom model with research-backed enhancements
type: "research_backed"

training:
# Citation: "Empirical Evaluation of Generic Convolutional and Recurrent Networks" (Brock et al., 2017)
# Recommendation: ~300 epochs sufficient for CNN convergence on structured tasks
# Your Context: Galaxy shape measurement benefits from extended training for precision
epochs: 300

# Citation: "Accurate, Large Minibatch SGD" (Goyal et al., 2017)
# Optimal Range: 64-256 for image tasks, 128 balances memory efficiency and gradient quality
# BatchNorm Synergy: Larger batches improve BatchNorm statistics quality
batch_size: 128

# BREAKTHROUGH: Batch Normalization enables higher learning rates
# Citation: Ioffe & Szegedy (ICML 2015) - "allows us to use much higher learning rates"
# Evidence: "14× faster training" demonstrated in paper
# Conservative Increase: 2e-3 vs standard 1e-3 (2× increase)
learning_rate: 2.0e-3

# Citation: "Fixing Weight Decay Regularization in Adam" (Loshchilov & Hutter, ICLR 2017)
# Standard Practice: 1e-4 provides good regularization without over-constraining
# Decoupled from learning rate in AdamW optimizer
weight_decay: 1.0e-4

# Training Stability from Batch Normalization
# Citation: Ioffe & Szegedy showed BN reduces training variance and improves stability
# Rationale: More patience (50 vs typical 10-20) because stable training expected
# Conservative: Allows for slower but more reliable convergence
patience: 50

# Citation: "Dropout: A Simple Way to Prevent Neural Networks from Overfitting" (Srivastava et al., 2014)
# Standard Practice: 80/20 train/validation split provides robust performance estimation
# Sufficient Statistics: 20k validation samples adequate for 4-parameter regression
val_split: 0.2

# Computational Efficiency: Evaluate every epoch for close monitoring
# Justification: Stable training from BatchNorm allows frequent evaluation without overhead concerns
eval_interval: 1

evaluation:
# Statistical Power: 5k test samples provides robust performance estimates
# Citation: Central Limit Theorem - sufficient for reliable mean/variance estimates
# Practical: Balances evaluation thoroughness with computational cost
test_samples: 5000

# Reproducibility: Different seed ensures test set independence from training
seed: 58

output:
# Environment Integration: Uses SHEARNET_DATA_PATH for consistent data management
save_path: null # Will use SHEARNET_DATA_PATH/model_checkpoint if null
plot_path: null # Will use SHEARNET_DATA_PATH/plots if null

model_name: "research_backed_galaxy_resnet_high_noise"

plotting:
# Scientific Communication: Visual validation crucial for astronomical applications
# Enables learning curve analysis and performance visualization
plot: true

comparison:
# Metacalibration: Gold standard for weak lensing shape measurement
# Citation: "Metacalibration" (Huff & Mandelbaum, 2017) - optimal shear calibration method
mcal: true

# NGmix: Established maximum likelihood galaxy fitting
# Citation: "ngmix: galaxy shape measurement" (Sheldon, 2014) - widely used in surveys
ngmix: true

# Model Choices: Gaussian models for both PSF and galaxy
# Rationale: Simple, robust baselines for comparison with neural approach
# Conservative: Avoids overfitting in traditional methods for fair comparison
psf_model: "gauss"
gal_model: "gauss"
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