Migrate timestamp format from YYYY-MM-DD-HH-MM-SS to YYYY-MM-DD_HH-MM-SS

Author: cool-RR

README.md

@@ -112,7 +112,7 @@ octane
 Use Octane to make figures for your paper:
 
 ```bash
-octane draw -t ~/.highjax/t/2026-03-15-20-02-25-101327 --epoch 300 -e 0 --timestep 19 --theme light \
+octane draw -t ~/.highjax/t/2026-03-15_20-02-25_101327 --epoch 300 -e 0 --timestep 19 --theme light \
   --zoom 1.8 --png ~/figure.png
 ```
 

docs/Octane/Octane overview.md

@@ -56,13 +56,13 @@ Data is loaded from `sample_es.parquet` (preferred, used by modern HighJax runs;
 
 ## Trek discovery
 
-On startup, Octane scans `~/.highjax/t/` (or `$HIGHJAX_HOME/t/`) for directories containing `meta.yaml` or `sample_es.parquet`. Results are sorted by directory name (timestamp format like `2026-01-31-02-13-44-322216`), so the most recent trek appears last.
+On startup, Octane scans `~/.highjax/t/` (or `$HIGHJAX_HOME/t/`) for directories containing `meta.yaml` or `sample_es.parquet`. Results are sorted by directory name (timestamp format like `2026-01-31_02-13-44_322216`), so the most recent trek appears last.
 
 Timing metadata comes from `meta.yaml`: `seconds_per_t` (policy timestep duration) and `seconds_per_sub_t` (sub-timestep duration, for environments with sub-stepping).
 
 ## Producing treks
 
-Treks are produced by running `highjax-trainer train`, which writes outputs to `~/.highjax/t/` (or `$HIGHJAX_HOME/t/`). Each training run creates a timestamped directory (e.g. `2026-01-31-02-13-44-322216`) containing `meta.yaml`, epoch data, and optionally `sample_es.parquet` with sampled episodes.
+Treks are produced by running `highjax-trainer train`, which writes outputs to `~/.highjax/t/` (or `$HIGHJAX_HOME/t/`). Each training run creates a timestamped directory (e.g. `2026-01-31_02-13-44_322216`) containing `meta.yaml`, epoch data, and optionally `sample_es.parquet` with sampled episodes.
 
 ## CLI usage
 
@@ -71,7 +71,7 @@ Treks are produced by running `highjax-trainer train`, which writes outputs to `
 octane
 
 # Open a specific trek
-octane -t ~/.highjax/t/2026-01-31-02-13-44-322216
+octane -t ~/.highjax/t/2026-01-31_02-13-44_322216
 
 # Open a breakdown parquet directly (auto-finds trek via meta.yaml)
 octane -t ~/.highjax/t/2026-.../breakdown/2026-..._a0_e200-200_.../es.parquet

docs/Trainer/Trainer training.md

@@ -92,7 +92,7 @@ All PPO hyperparameters live in `AgentConfig`:
 Training with trek enabled (the default) creates a timestamped directory under `~/.highjax/t/` (or `$HIGHJAX_HOME/t/`). Set `$HIGHJAX_HOME` to override the default `~/.highjax/` root. All data (treks, behaviors, config, logs) will use `$HIGHJAX_HOME/` instead.
 
 ```
-~/.highjax/t/2026-03-15-20-02-25-101327/
+~/.highjax/t/2026-03-15_20-02-25_101327/
   meta.yaml      # Environment config, git info, parameter counts
   sample_es.pq   # Sampled episode trajectories
   epochia.pq     # Epoch-level metrics

highjax_trainer/ozette/metadata.py

@@ -21,7 +21,7 @@ def sanitize_for_filename(s: str, max_len: int = 50) -> str:
 
 def make_log_filename(timestamp: datetime.datetime, argv: Optional[list[str]] = None) -> str:
     '''Create log filename from timestamp and optional argv.'''
-    ts_str = timestamp.strftime('%Y-%m-%d-%H-%M-%S')
+    ts_str = timestamp.strftime('%Y-%m-%d_%H-%M-%S')
 
     if argv and len(argv) > 1:
         cmd_str = ' '.join(argv[1:])

highjax_trainer/trekking.py

@@ -32,7 +32,7 @@ def _get_highjax_treks() -> pathlib.Path:
 def _make_timestamp_name() -> str:
     now = datetime.datetime.now()
     return (
-        now.strftime('%Y-%m-%d-%H-%M-%S-') + f'{now.microsecond:06d}'
+        now.strftime('%Y-%m-%d_%H-%M-%S_') + f'{now.microsecond:06d}'
     )
 
 

octane/src/cli.rs

@@ -21,7 +21,7 @@ use crate::render::RenderConfig;
 use crate::util::{find_parquet_file, posh_path};
 
 /// Find the most recent trek in ~/.highjax/t/.
-/// Treks are directories with timestamp names (e.g., 2026-01-31-02-13-44-322216).
+/// Treks are directories with timestamp names (e.g., 2026-01-31_02-13-44_322216).
 /// Selects the newest by directory name.
 fn find_latest_trek() -> Option<PathBuf> {
     let home = std::env::var("HOME").ok()?;

octane/src/data/trek.rs

@@ -540,7 +540,7 @@ pub struct ParquetSource {
     /// Short display name (e.g. "sample_es" or breakdown run name) for UI.
     pub display: String,
     /// Path relative to trek root (e.g. "sample_es.parquet" or
-    /// "breakdown/2026-02-20-13-07-24_a0_e100-100_mm500_jfj/es.parquet").
+    /// "breakdown/2026-02-20_13-07-24_a0_e100-100_mm500_jfj/es.parquet").
     /// Used for `-t` CLI matching when target is a parquet file.
     pub relative_path: String,
 }

octane/src/leona/src/lib.rs

@@ -71,7 +71,7 @@ pub fn init(config: LogConfig) -> Result<PathBuf> {
 
     // Generate log filename with timestamp
     let now = Local::now();
-    let timestamp = now.format("%Y-%m-%d-%H-%M-%S");
+    let timestamp = now.format("%Y-%m-%d_%H-%M-%S");
     let log_filename = format!("{timestamp}_{}.log", config.app_name);
     let log_path = logs_dir.join(&log_filename);
 

tests/test_highjax_trainer/test_ozette/test_core.py

@@ -207,7 +207,7 @@ def test_log_path_format(self, temp_base_dir):
         log_path = ozette.get_log_path()
         assert log_path.parent.name == 'logs'
         assert log_path.parent.parent.name == '.test_path_fmt'
-        assert re.match(r'\d{4}-\d{2}-\d{2}-\d{2}-\d{2}-\d{2}', log_path.name)
+        assert re.match(r'\d{4}-\d{2}-\d{2}_\d{2}-\d{2}-\d{2}', log_path.name)
         assert log_path.name.endswith('.log')
 
     def test_install_returns_instance(self, temp_base_dir):

tests/test_highjax_trainer/test_trekking.py

@@ -80,6 +80,6 @@ def test_create_trek_timestamp_format(self, tmp_path, env_and_params,
         monkeypatch.setenv('HIGHJAX_HOME', str(tmp_path))
         trek_path = create_trek(env, params, agent_config)
         name = trek_path.name
-        pattern = r'^\d{4}-\d{2}-\d{2}-\d{2}-\d{2}-\d{2}-\d{6}$'
+        pattern = r'^\d{4}-\d{2}-\d{2}_\d{2}-\d{2}-\d{2}_\d{6}$'
         assert re.match(pattern, name), f'Name {name!r} does not match timestamp pattern'
         assert trek_path.parent == tmp_path / 't'