tract7dt 0.3.2

7DT image-specific Tractor photometry pipeline

tract7dt

7DT image-specific Tractor photometry pipeline.
This distribution is licensed under MIT.

Installation

1. Install Tractor (see https://github.com/dstndstn/tractor; however the upstream README seems outdated; use the recommended steps below).
2. Install this package:

python -m pip install tract7dt

astrometry.net and Tractor must be installed in advance. Python prerequisites such as numpy, scipy, astropy, photutils, sep, matplotlib, fitsio, emcee, and PyYAML are declared as dependencies.

Tractor installation (recommended)

1) Conda environment

conda create -n {envname} python=3.11 -y
conda activate {envname}

2) System dependencies (apt)

sudo apt update
sudo apt install -y build-essential python3-dev git pkg-config \
    libcfitsio-dev libeigen3-dev swig libceres-dev \
    libgoogle-glog-dev libgflags-dev libsuitesparse-dev

3) Python build tools + scientific stack

pip install -U pip setuptools wheel cython numpy scipy fitsio emcee matplotlib

4) astrometry.net (required by Tractor)

conda install -c conda-forge astrometry -y

5) Tractor build (Cython + Ceres enabled)

git clone https://github.com/dstndstn/tractor.git
cd tractor
python setup.py build_ext --inplace --with-ceres --with-cython
pip install . --no-build-isolation

6) Verify install

python -c "import tractor; print(tractor.__version__)"
python -c "from tractor.ceres_optimizer import CeresOptimizer; print('CeresOptimizer OK')"
python examples/tractor-sdss-synth.py

Quick start

1) Create a YAML config

# Writes sample_config.yaml in the current directory by default.
tract7dt dump-config

# Or write to a specific path.
tract7dt dump-config --out sample_config.yaml

# Use --force to overwrite an existing file.
tract7dt dump-config --force

2) Download sample image data for test runs

# Download under current directory with original dataset folder name.
tract7dt download-sample-data

# Or set an explicit dataset directory path.
tract7dt download-sample-data --dir "/path/to/sample_data_dir"

# Overwrite an existing target dataset directory.
tract7dt download-sample-data --dir "/path/to/sample_data_dir" --force

Without --dir, the command creates the dataset under the current directory using the archive's original dataset folder name.
With --dir /path/to/sample_data_dir, the dataset directory is created at that exact path.
In both cases, FITS names are standardized to 7DT_UDS_m***.fits and image_list.txt is generated with absolute paths.

Maintainers can control source asset defaults via:

• TRACT7DT_SAMPLE_REPO
• TRACT7DT_SAMPLE_TAG
• TRACT7DT_SAMPLE_ASSET
• optional checksum: TRACT7DT_SAMPLE_SHA256

3) Edit required config paths

At minimum, set:

• inputs.tile_name
• inputs.input_catalog
• inputs.image_list_file
• inputs.gaiaxp_synphot_csv
• outputs.work_dir

4) Run the full pipeline

tract7dt run --config /path/to/config.yaml

Role of the config file

• The YAML config centralizes runtime decisions (inputs, outputs, checks, ePSF behavior, patch options, merge behavior, logging, performance knobs).
• tract7dt run --config ... reads this single file and executes the full step chain.
• Subcommands share the same config model, so one file can drive full runs and partial reruns consistently.

For full command/config/behavior reference, see the docs in docs/ (or publish with Read the Docs using .readthedocs.yaml).