it works

.....I think

package-lock.json

@@ -0,0 +1,24 @@
+{
+  "name": "PhD-Rainfall-Radar",
+  "lockfileVersion": 2,
+  "requires": true,
+  "packages": {
+    "": {
+      "dependencies": {
+        "duplex-child-process": "^1.0.1"
+      }
+    },
+    "node_modules/duplex-child-process": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/duplex-child-process/-/duplex-child-process-1.0.1.tgz",
+      "integrity": "sha512-tWbt4tyioDjyK5nh+qicbdvBvNjSXsTUF5zKUwSauuKPg1mokjwn/HezwfvWhh6hXoLdgetY+ZlzU/sMwUMJkg=="
+    }
+  },
+  "dependencies": {
+    "duplex-child-process": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/duplex-child-process/-/duplex-child-process-1.0.1.tgz",
+      "integrity": "sha512-tWbt4tyioDjyK5nh+qicbdvBvNjSXsTUF5zKUwSauuKPg1mokjwn/HezwfvWhh6hXoLdgetY+ZlzU/sMwUMJkg=="
+    }
+  }
+}

package.json

@@ -0,0 +1,5 @@
+{
+  "dependencies": {
+    "duplex-child-process": "^1.0.1"
+  }
+}

rainfallwrangler/src/lib/RadarWrangler.mjs

@@ -27,7 +27,6 @@ class RadarWrangler {
 			
 			const result = this.make_sample(timestep_buffer);
 			if(result == null) continue;
-			
 			yield result;
 			
 			timestep_buffer.shift();
@@ -50,7 +49,7 @@ class RadarWrangler {
 			offset += channel_timestep_count;
 		}
 		
-		return grouped_timesteps;
+		return Promise.all(grouped_timesteps);
 	}
 }
 

rainfallwrangler/src/lib/io/RecordWrangler.mjs

@@ -6,6 +6,7 @@ import path from 'path';
 import RecordBuilder from '../record/RecordBuilder.mjs';
 import RecordsWriter from '../record/RecordsWriter.mjs';
 import pretty_ms from 'pretty-ms';
+import terrain50_analyse_frequencies from 'terrain50/src/static/Terrain50AnalyseFrequencies.mjs';
 
 class RecordWrangler {
 	#builder = new RecordBuilder();
@@ -14,6 +15,8 @@ class RecordWrangler {
 		this.dirpath = dirpath;
 		this.count_per_file = count_per_file;
 		
+		this.display_interval = 2 * 1000;
+		
 		if(!fs.existsSync(this.dirpath))
 			fs.mkdirSync(this.dirpath);
 	}
@@ -22,24 +25,23 @@ class RecordWrangler {
 		// TODO: Shuffle stuff about in the *Python* data pipeline
 		
 		let writer = null;
-		let i = -1, i_file = 0, count_this_file = 0, time_start = new Date();
+		let i = 0, i_file = 0, count_this_file = 0, time_start = new Date(), time_display = time_start;
 		while(true) {
 			i++;
 			
-			console.log(`RecordWriter step ${i}`);
-			
 			// Start writing to a new file when necessary
 			if(writer == null || count_this_file > this.count_per_file) {
 				if(writer !== null) await writer.close();
 				const filepath_next = path.join(this.dirpath, `${i_file}.jsonl.gz`);
 				writer = new RecordsWriter(filepath_next);
-				console.log(`RecordWriter NEW FILE ${filepath_next}`);
 				i_file++;
+				count_this_file = 0;
 			}
 			
+			count_this_file++;
+			
 			const sample_radar = await reader_radar.next();
 			const sample_water = await reader_water.next();
-			
 			if(sample_radar.done || sample_water.done) break;
 			
 			const example_next = this.make_example(
@@ -49,14 +51,19 @@ class RecordWrangler {
 			
 			await writer.write(example_next);
 			
-			process.stderr.write(`Elapsed: ${pretty_ms(new Date() - time_start)}, Written ${count_this_file}/${i_file}/${i} examples/files/total\r`);
+			const time_now = new Date();
+			if(time_now - time_display > this.display_interval) {
+				const elapsed = new Date() - time_start;
+				process.stderr.write(`Elapsed: ${pretty_ms(elapsed, { keepDecimalsOnWholeSeconds: true })}, Written ${count_this_file}/${i_file}/${i} examples/files/total | ${(1000 / (elapsed / i)).toFixed(2)} batches/sec | ${this.count_per_file - count_this_file} left for this file\r`);
+				time_display = time_now;
+			}
 		}
 		
 	}
 	
 	make_example(sample_radar, sample_water) {
 		this.#builder.add("rainfallradar", sample_radar);
-		this.#builder.add("waterdepth", sample_water.flat);
+		this.#builder.add("waterdepth", sample_water);
 		return this.#builder.release();
 	}
 }

rainfallwrangler/src/lib/manip/array2d_pool.mjs

@@ -12,7 +12,6 @@ export default async function array2d_pool(channels, operator="max") {
 		const tensor = tf.tensor(channels);
 		return tf.max(tensor, 0, false);
 	});
-	
 	const result_array = await result_tensor.array();
 	result_tensor.dispose();
 	

rainfallwrangler/src/lib/record/RecordsWriter.mjs

@@ -2,21 +2,22 @@
 
 import fs from 'fs';
 
-import SpawnStream from 'spawn-stream';
+import ChildProcess from 'duplex-child-process';
 
 import { write_safe, end_safe } from '../io/StreamHelpers.mjs';
 
 class RecordsWriter {
-	#stream_out = fs.createWriteStream(filepath);
-	#gzip = SpawnStream("gzip");
+	#stream_out = null;
+	#gzip = ChildProcess.spawn("gzip");
 	
 	constructor(filepath) {
+		this.#stream_out = fs.createWriteStream(filepath);
 		this.#gzip.pipe(this.#stream_out);
 	}
 	
 	async write(sample) {
-		console.log(sample);
-		await write_safe(this.#gzip, JSON.stringify(sample));
+		const str = JSON.stringify(Object.fromEntries(sample));
+		await write_safe(this.#gzip, str);
 	}
 	
 	async close() {