HERA Validation Repository

Archive of formal software pipeline validation tests

This repository contains code and documentation for formal tests of the HERA software pipeline. Tests are typically performed and documented as Jupyter notebooks and are archived to provide a long-standing account of the accuracy of the pipeline as it evolves. Directory structures define the broad kinds of tests performed.

Mission Statement

The validation group seeks to validate the HERA data pipeline software and algorithms by testing the specific software against simulations where the expected output is well understood theoretically.The group also helps to develop and define increasingly sophisticated simulations on which to build an end-to-end test and validation of the HERA pipeline.

Structure of this repository

The validation effort seeks to verify the HERA software pipeline through a number of well-defined steps of increasing complexity. Each of these steps (called major steps or just steps in this repository) reflects a broad validation concern or a specific element of the pipeline. For example, step 0 seeks to validate just the hera_pspec software when given a well-known white-noise P(k)-generated sky.

Within each step exists the possibility of a set of variations (called minor variations or just variations in this repo). For example, variations for step 0 may be to generate flat-spectrum P(k) and non-flat P(k).

Finally, each combination of step-variation has the potential to incur several staged tests or trials (we call them trials in the repo).

Importantly, failing trials will not be removed/overwritten in this repo. Each formally-run trial is archived here for posterity.

Thus the structure for this repo is as follows: Under the test-series directory, a number of directories labelled simply with their corresponding step number are housed. Within each of these directories, each actual trial is presented as a notebook labelled test-<step>.<variation>.<trial>.ipynb.

All steps, variations and trials are assigned increasing numerical values. Generally, these values are increasing (from 0) in order of time/complexity.

In addition to the trial notebooks in these directories, each directory will contain a README.md which lists the formal goals and conditions of each of its variations.

Finally, each variation will be represented as a specific Github project, in which the progress can be tracked and defined. Each project should receive a title which contains the step.variation identifier as well as a brief description.

Writing a validation test notebook

We have provided a template notebook which should serve as a starting place for creating a validation notebook. The template is self-describing, and has no intrinsic dependencies. All text in the notebook surrounded by curly braces are meant to be replaced.

The template can be slightly improved/cleaned if you use jupyter notebook extensions -- in particular the ToC and python-markdown extensions. The first allows a cleaner way to build a table of contents (though one is already included), and the latter allows using python variables in markdown cells. This makes the writing of git hashes and versions simpler, and means for example that the execution time/date can be written directly into a markdown cell.

Project Plan

To create a simple tabulated version of the Project Plan, download the repo, save a personal access token to a file called .pesonal-github-token, (ensure there is no trailing "\n" in the file) and run make_project_table.py at the root directory. Note that you will need python 3.4+ and the pygithub code to run this script (pip install pygithub). A semi-up-to-date version of this table is found at project_table.md.

H1C Sims

The data for the H1C sims reported in the H1C IDR2 Validation (Aguirre et al., 2021) are available upon reasonable request. For collaboration members, the paths on the NRAO machines are listed below.

There are three main versions of the simulated data, for different levels of processing:

1. Daily raw visibilities (equivalent to raw HERA observations in terms of format/content)
2. Daily "processed" visibilities (processed by some portion of the analysis pipeline)
3. LST-binned data suitable for power spectrum analysis.

The simulated data has the following properties (see above linked paper for details):

• EoR is a Gaussian Random Field with power-law power spectrum
• Foregrounds are GLEAM + eGSM
• 10 full days were simulated (nominally 245 + [8098, 8099, 8101, 8102, 8103, 8106, 8107, 8108, 8110, 8111])
• Visibility Simulator was RIMEz
• Primary Beam was Fagnoni+2019 HERA beam model
• Simulations consist of a strict subset of H1C antennas / baselines
• Frequency range/resolution is the same as H1C data (i.e. 100-200 MHz in 1024 channels)
• Systematics applied to the data (where appropriate) are:
  • Thermal Noise: based on constant receiver noise plus simulated autos
  • Bandpass Gains: randomly perturbed around H1C bandpass measurements
  • Cable Reflections
  • Cross-coupling

Below, we specify for each of the three data versions where to find the data.

Daily Raw Visibilities

These reside in /lustre/aoc/projects/hera/Validation/test-4.0.0/data/visibilities/245*/ (one folder per day of mock-observation). The files in each of these directories follow this naming convention: zen.{jd_major}.{jd_minor}.{sky_component}.{state}.uvh5.
The {sky_component} indicates which sky models are present in the data, and can be one of

• eor: The EoR.
• foregrounds: The Foregrounds (both GLEAM and eGSM)
• sum: Both EoR and Foregrounds

The {state} indicates whether the state of the data in terms of systematics, and can be one of

• true: No systematics included (including noise)
• corrupt: All systematics included (see above list)
• uncal: only bandpass gains included.

For example, the command ls zen.2458098.32685.* yields:

zen.2458098.32685.eor.true.uvh5
zen.2458098.32685.foregrounds.corrupt.uvh5
zen.2458098.32685.foregrounds.true.uvh5
zen.2458098.32685.sum.corrupt.uvh5
zen.2458098.32685.sum.true.uvh5
zen.2458098.32685.sum.uncal.ref_uncal.uvh5
zen.2458098.32685.sum.uncal.uvh5

Daily Processed Visibilities

We assume most users are not interested in this step, but it is included for completeness.

These partially-processed visibilities are in /lustre/aoc/projects/hera/Validation/test-4.0.0/pipeline/245{jd}_{kind}/, where {kind} represents which data was input to the processing, and can be one of

• foregrounds: Just foregrounds (no EoR) with all systematics
• sum: FG+EoR with all systematics
• sum_uncal: FG+EoR with just bandpass gains but not other systematics

Other combinations of mock observations (eg. eor.corrupt) were not processed.

Each of these folders contains a number of files. Each file corresponds to a stage/product of processing, such as firstcal, abscal, smoothcal etc. For example, the files in /lustre/aoc/projects/hera/Validation/test-4.0.0/pipeline/2458098_foregrounds/ are:

2458098_foregrounds/zen.2458098.49089.foregrounds.corrupt.abs.calfits
2458098_foregrounds/zen.2458098.49089.foregrounds.corrupt.autos.uvh5
2458098_foregrounds/zen.2458098.49089.foregrounds.corrupt.first.calfits
2458098_foregrounds/zen.2458098.49089.foregrounds.corrupt.firstcal_metrics.hdf5
2458098_foregrounds/zen.2458098.49089.foregrounds.corrupt.flagged_abs.calfits
2458098_foregrounds/zen.2458098.49089.foregrounds.corrupt.flagged_abs_vis.uvh5
2458098_foregrounds/zen.2458098.49089.foregrounds.corrupt.noise_std.uvh5
2458098_foregrounds/zen.2458098.49089.foregrounds.corrupt.omni.calfits
2458098_foregrounds/zen.2458098.49089.foregrounds.corrupt.omni_vis.uvh5
2458098_foregrounds/zen.2458098.49089.foregrounds.corrupt.smooth_abs.calfits
2458098_foregrounds/zen.2458098.49089.foregrounds.corrupt.smooth_abs_vis.uvh5
2458098_foregrounds/zen.2458098.49089.foregrounds.corrupt.uvh5
2458098_foregrounds/zen.2458098.49089.foregrounds.corrupt.calibrated.ms
2458098_foregrounds/zen.2458098.49089.foregrounds.corrupt.calibrated.uvh5_image

The fully-processed files end with .smooth_abs_vis.uvh5.

LST-Binned Data

The final LST-binned data suitable for power spectrum analysis is in /lustre/aoc/projects/hera/Validation/test-4.0.0/pipeline/LSTBIN/.
Within this directory, the LST-binned data for different combinations of input models and processing is kept in different directories, namely:

• sum/: FG+EoR, systematics applied, then calibrated out.
• foregrounds/: FG-only (no EoR), systematics appplied, then calibrated out.
• true_eor/: EoR-only, no systematics applied
• true_foregrounds/: FG-only, no systematics applied
• true_sum/: FG+EoR, no systematics applied

In particular, no EoR-only with systematics was produced.

In each directory there are a great number of files. The most important files (i.e the LST-binned and pre-processed visibilities) have the filename convention zen.grp1.of1.LST.{lst}.HH.{processing_tags}.uvh5. Here the lst is a floating point number giving the LST in radians. The {processing_tags} are a group of single upper-case characters that indicate which processing steps have been applied. They are:

• O: omnical
• C: abscal
• R: RFI
• S: smoothcal
• L: LST binned
• P: in-painted
• X: cross-talk mitigated
• T: time averaged
• K: pseudo-Stokes

For example, doing ls LSTBIN/foregrounds/zen.grp1.of1.LST.*.HH.O*.uvh5 gives

LSTBIN/foregrounds/zen.grp1.of1.LST.0.28190.HH.OCRSLP.uvh5     LSTBIN/foregrounds/zen.grp1.of1.LST.1.03362.HH.OCRSL.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.28190.HH.OCRSL.uvh5      LSTBIN/foregrounds/zen.grp1.of1.LST.1.03441.HH.OCRSLPX.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.28268.HH.OCRSLPX.uvh5    LSTBIN/foregrounds/zen.grp1.of1.LST.1.12759.HH.OCRSLP.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.28973.HH.OCRSLPXTK.uvh5  LSTBIN/foregrounds/zen.grp1.of1.LST.1.12759.HH.OCRSL.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.28973.HH.OCRSLPXT.uvh5   LSTBIN/foregrounds/zen.grp1.of1.LST.1.12837.HH.OCRSLPX.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.37586.HH.OCRSLP.uvh5     LSTBIN/foregrounds/zen.grp1.of1.LST.1.22156.HH.OCRSLP.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.37586.HH.OCRSL.uvh5      LSTBIN/foregrounds/zen.grp1.of1.LST.1.22156.HH.OCRSL.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.37665.HH.OCRSLPX.uvh5    LSTBIN/foregrounds/zen.grp1.of1.LST.1.22234.HH.OCRSLPX.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.46983.HH.OCRSLP.uvh5     LSTBIN/foregrounds/zen.grp1.of1.LST.1.22939.HH.OCRSLPXTK.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.46983.HH.OCRSL.uvh5      LSTBIN/foregrounds/zen.grp1.of1.LST.1.22939.HH.OCRSLPXT.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.47061.HH.OCRSLPX.uvh5    LSTBIN/foregrounds/zen.grp1.of1.LST.1.31552.HH.OCRSLP.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.56380.HH.OCRSLP.uvh5     LSTBIN/foregrounds/zen.grp1.of1.LST.1.31552.HH.OCRSL.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.56380.HH.OCRSL.uvh5      LSTBIN/foregrounds/zen.grp1.of1.LST.1.31631.HH.OCRSLPX.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.56458.HH.OCRSLPX.uvh5    LSTBIN/foregrounds/zen.grp1.of1.LST.1.40949.HH.OCRSLP.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.60295.HH.OCRSLPXTK.uvh5  LSTBIN/foregrounds/zen.grp1.of1.LST.1.40949.HH.OCRSL.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.60295.HH.OCRSLPXT.uvh5   LSTBIN/foregrounds/zen.grp1.of1.LST.1.41027.HH.OCRSLPX.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.65776.HH.OCRSLP.uvh5     LSTBIN/foregrounds/zen.grp1.of1.LST.1.50345.HH.OCRSLP.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.65776.HH.OCRSL.uvh5      LSTBIN/foregrounds/zen.grp1.of1.LST.1.50345.HH.OCRSL.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.65854.HH.OCRSLPX.uvh5    LSTBIN/foregrounds/zen.grp1.of1.LST.1.50424.HH.OCRSLPX.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.75173.HH.OCRSLP.uvh5     LSTBIN/foregrounds/zen.grp1.of1.LST.1.54261.HH.OCRSLPXTK.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.75173.HH.OCRSL.uvh5      LSTBIN/foregrounds/zen.grp1.of1.LST.1.54261.HH.OCRSLPXT.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.75251.HH.OCRSLPX.uvh5    LSTBIN/foregrounds/zen.grp1.of1.LST.1.59742.HH.OCRSLP.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.84569.HH.OCRSLP.uvh5     LSTBIN/foregrounds/zen.grp1.of1.LST.1.59742.HH.OCRSL.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.84569.HH.OCRSL.uvh5      LSTBIN/foregrounds/zen.grp1.of1.LST.1.59820.HH.OCRSLPX.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.84648.HH.OCRSLPX.uvh5    LSTBIN/foregrounds/zen.grp1.of1.LST.1.69139.HH.OCRSLP.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.91617.HH.OCRSLPXTK.uvh5  LSTBIN/foregrounds/zen.grp1.of1.LST.1.69139.HH.OCRSL.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.91617.HH.OCRSLPXT.uvh5   LSTBIN/foregrounds/zen.grp1.of1.LST.1.69217.HH.OCRSLPX.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.93966.HH.OCRSLP.uvh5     LSTBIN/foregrounds/zen.grp1.of1.LST.1.78535.HH.OCRSLP.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.93966.HH.OCRSL.uvh5      LSTBIN/foregrounds/zen.grp1.of1.LST.1.78535.HH.OCRSL.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.0.94044.HH.OCRSLPX.uvh5    LSTBIN/foregrounds/zen.grp1.of1.LST.1.78613.HH.OCRSLPX.uvh5
LSTBIN/foregrounds/zen.grp1.of1.LST.1.03362.HH.OCRSLP.uvh5

Long-Term Data Storage

Data for all tests is not stored in this repo, but principally on the NRAO machine, at /lustre/aoc/projects/hera/Validation/. Each specific test has its own directory with its associated data (eg. Validation/test-1.0.0/). The paths to the data within this directory for each test are explicitly referred to in the corresponding test notebook included in this repo. In general, visibilities required for the test will be in the visibilities/ directory, in *.uvh5 files, while power spectra will be in the spectra/ directory, in *.psc files. However, different tests require different hierarchies of data, so always refer to the notebook for details.

Also, be aware that some of the files within these directories will be symbolic links to data stored for other tests. This eases the burden of storage while maintaining a logical file layout for each test.

Given the size of the data, and the infrequency of its usage, we maintain a backup of the larger data products on the librarian storage system, and purge the files from lustre except at need. They are at /home/herastore02-1/Validation/. Even so, they are symlinked to their standard places on lustre, so they can be accessed in the usual manner described above.