Accuracy target for higher precision and tweaks for check_accuracy stability

.devcontainer/Dockerfile

@@ -19,6 +19,7 @@ RUN apt-get update \
     libgsl-dev \
     make \
     pkg-config \
+    ripgrep \
     tar \
     unzip \
     xz-utils \
@@ -42,6 +43,7 @@ RUN mkdir -p \
         wheel \
         findent \
         fortls \
+        matplotlib \
         numpy \
         scipy \
         sympy \

.devcontainer/README.md

@@ -62,3 +62,6 @@ devcontainer's selected interpreter may need to be pointed explicitly at
 `/home/vscode/.local/share/camb-devcontainer/.venv/bin/python3`.
 
 If you explicitly want a standards-based editable install after the container is up, you can still run `python -m pip install --no-build-isolation --no-deps -e .`, but that setuptools metadata phase is the part that remains slow on this bind-mounted checkout.
+
+
+The container includes CosmoRec and HyRec. If not needed, you can speed builds by doing `export RECOMBINATION_FILES=recfast`

.devcontainer/devcontainer.json

@@ -10,6 +10,9 @@
   "runArgs": [
     "--cpus=8"
   ],
+  "features": {
+    "ghcr.io/anthropics/devcontainer-features/claude-code:1.0": {}
+  },
   "workspaceMount": "source=${localWorkspaceFolder}/..,target=/workspaces/camb-parent,type=bind",
   "workspaceFolder": "/workspaces/camb-parent/${localWorkspaceFolderBasename}",
   "mounts": [

.github/workflows/tests.yml

@@ -59,7 +59,7 @@ jobs:
       - name: Run tests
         run: |
           python -c "import camb; print(camb.__version__)"
-          python -m unittest camb.tests.camb_test
+          python -c "import os, subprocess, sys; modules=['camb.tests.camb_test']; modules += [] if os.getenv('CAMB_TEST_FAST') else ['camb.tests.camb_test_slow']; print('Running', ', '.join(modules)); subprocess.run([sys.executable, '-m', 'unittest', *modules], check=True)"
 
       - name: HM code tests
         if: matrix.os == 'ubuntu-latest'

.gitignore

@@ -56,6 +56,7 @@ testfile*
 .vs
 *.mp4
 *.exe
+*_tmp*
 
 # Ignore all .dat and .ini files except those already tracked in git
 *.dat
@@ -89,3 +90,4 @@ external/
 !.devcontainer/
 !.devcontainer/**
 .claude
+devcontainer-lock.json

AGENTS.md

@@ -1,20 +1,52 @@
-# Project instructions
-- This is the CAMB python cosmology code source, wrapping fortran 2003 for numerics
-- Follow the rules in this file.
-- If `AGENTS.local.md` exists, read it after this file and let it override local environment details.
-
-# Project rules and guidance
-- Python uses python 3.10+ with modern type hint syntax
-- Use double-quotes for strings; line length 120
-- Code is auto-formatted by ruff, including import reordering.
-- Fortran uses modern Fortran 2003, compiled with gfortran or ifort
-- Install and run pre-commit hooks as needed for checking
-- /forutils is a git submodule with shared fortran utilities and classes
-- For fortran/wrapped fortran code modifications see /docs/modifying_code.rst
-- When updating version, update both python __version__ and version defined near the top of fortran/config.f90
-- Use pip -e for editable first install. After that use "python setup.py make" to quickly rebuild fortran for use with python.
-- Default test: python -m unittest camb.tests.camb_test (do not run hmcode_test unless specifically relevant)
-- Long test against precomputed results: fortran/tests/run_tests.py which calls CAMB_test_files.py (only if asked)
-- Installation/clone/modification/contributing/pre-commit/vscode config: see /CONTRIBUTING.md
-- When plotting fractional differences for cross-spectra, use e.g. Delta TE/sqrt(TT*EE)
-- High accuracy lensing needs lens_potential_accuracy = 8 or so (mainly increases kmax)
+# Project Overview
+
+This is the CAMB Python cosmology code, wrapping Fortran 2003 for numerics.
+
+---
+
+# Coding Standards
+
+## Python
+- Use Python 3.10+ with modern type-hint syntax.
+- Use double-quotes for strings; maximum line length is 120.
+- Code is auto-formatted by **ruff**, including import reordering.
+- Use the **pre-commit** command line to run ruff check/format (e.g., `pre-commit run --all-files`); do not invoke `ruff` directly.
+- Ruff/pyupgrade hooks and their configuration live in `.pre-commit-config.yaml`
+- All code must be Python or Fortran only—no bash scripts except for devcontainer setup and GitHub Actions.
+
+## Fortran
+- Use modern Fortran 2003, compiled with **gfortran** or **ifort**.
+- `/forutils` is a git submodule containing shared Fortran utilities and classes.
+- For guidance on modifying Fortran or wrapped Fortran code, see `/docs/modifying_code.rst`.
+
+---
+
+# Development Workflow
+
+## Installation & Build
+- Use `pip install -e .` for the initial editable install.
+- After the first install, use `python setup.py make` to quickly rebuild the Fortran for use with Python after any fortran changes.
+- If `python setup.py make` produces stale `.mod` type-mismatch errors, run `python setup.py clean` first (not normally needed).
+
+## Testing
+- **Default test:** `python -m unittest camb.tests.camb_test`.
+  - Do **not** run `camb.tests.hmcode_test` unless specifically relevant.
+- **Long test** against precomputed results: `python fortran/tests/run_tests.py`, which calls `CAMB_test_files.py`. Only run this if explicitly asked.
+
+## Configuration
+- See `CONTRIBUTING.md` for installation, cloning, modification guidelines, contribution instructions, pre-commit setup, and VS Code configuration.
+
+---
+
+# Maintenance & Versioning
+- When updating the version, update **both**:
+  - the Python `__version__`, and
+  - the version defined near the top of `fortran/config.f90`.
+- When adding new `.ini` file parameters, also add the corresponding `.ini` write logic in `camb/_ini.py`.
+
+---
+
+# Physics & Numerical Guidance
+- When plotting fractional differences for cross-spectra, use e.g. $\Delta TE / \sqrt{TT \cdot EE}$.
+- High-accuracy lensing requires `lens_potential_accuracy = 8` or so (this mainly increases `kmax`).
+- Use `camb/check_accuracy.py` to assess numerical stability by comparing a default run to a high-accuracy run.

CONTRIBUTING.md

@@ -63,6 +63,14 @@ Run the test suite to ensure your changes don't break anything:
 python -m unittest camb.tests.camb_test
 ```
 
+To run the full suite including the slower symbolic and emission-angle tests:
+
+```bash
+python -m unittest camb.tests.camb_test camb.tests.camb_test_slow
+```
+
+The GitHub workflows include `camb.tests.camb_test_slow` by default, and skip it when `CAMB_TEST_FAST` is set.
+
 For HMcode tests (Linux only):
 
 ```bash

camb/__init__.py

@@ -8,13 +8,20 @@
 __author__ = "Antony Lewis"
 __contact__ = "antony at cosmologist dot info"
 __url__ = "https://camb.readthedocs.io"
-__version__ = "1.6.7"
+__version__ = "1.6.8"
 
 from . import baseconfig
 
 baseconfig.check_fortran_version(__version__)
 from . import dark_energy, initialpower, model, nonlinear, reionization
-from ._config import config
+from ._config import (
+    config,
+    lensing_method_curv_corr,
+    lensing_method_curv_corr_direct,
+    lensing_method_flat_corr,
+    lensing_method_harmonic,
+    lensing_method_optimized,
+)
 from .baseconfig import (
     Array1D,
     CAMBError,

camb/_config.py

@@ -6,12 +6,25 @@
 lensing_method_curv_corr = 1
 lensing_method_flat_corr = 2
 lensing_method_harmonic = 3
+lensing_method_curv_corr_direct = 4
+lensing_method_optimized = 5
 
 
 class _config:
     # print feedback if > 0 (note in Jupyter notebook this will appear in the terminal, not the notebook)
     FeedbackLevel = import_property(c_int, "config", "FeedbackLevel")
 
+    # enable targeted accuracy improvements if > 0, AccuracyTarget being SO-like.
+    AccuracyTarget = import_property(c_int, "config", "AccuracyTarget")
+
+    near_flat_approx_chi_limit = import_property(c_double, "config", "near_flat_approx_chi_limit")
+
+    near_flat_approx_chidisp_limit = import_property(c_double, "config", "near_flat_approx_chidisp_limit")
+
+    enable_do_near_flat_integration = import_property(c_bool, "config", "enable_do_near_flat_integration")
+
+    enable_shifted_q_scalar_approx = import_property(c_bool, "config", "enable_shifted_q_scalar_approx")
+
     # print additional timing and progress (when FeedbackLevel>0)
     DebugMsgs = import_property(c_bool, "config", "DebugMsgs")
 

camb/_ini.py

@@ -258,6 +258,7 @@ def _update_ini_state_from_params(params: model.CAMBparams, state: CambIniFile)
     if params.WantCls and (params.WantScalars or params.WantVectors):
         set_param(state, "l_max_scalar", params.max_l)
         set_param(state, "k_eta_max_scalar", params.max_eta_k)
+        set_param(state, "lens_output_margin", params.lens_output_margin)
         if params.WantScalars:
             set_param(state, "do_lensing", params.DoLensing)
     if params.WantCls and params.WantTensors: