| |
| """LM4 电磁波持续学习 — NASA CDAWeb (Van Allen Probes RBSP-A) 数据下载 |
| |
| 数据源 (HAPI 2.0): |
| - RBSP-A_DENSITY_EMFISIS-L4 : 等离子体密度 + 磁场 + 特征频率 (6秒) |
| - RBSP-A_MAGNETOMETER_1SEC-GEI_EMFISIS-L3 : 三分量磁场 (1秒) |
| |
| 输出: 每个月一个 .npz, 含对齐后的 时间/密度/磁场/等离子体特征 |
| |
| 用法: |
| python3 download_wave_data.py --start 2015-01 --months 3 |
| """ |
| import os, sys, json, time, argparse, urllib.request, urllib.error |
| from datetime import datetime, timedelta, timezone |
|
|
| HAPI = "https://cdaweb.gsfc.nasa.gov/hapi/data" |
| OUT_DIR = os.path.join(os.path.dirname(os.path.abspath(__file__)), "..", "data", "wave") |
|
|
|
|
| def fetch(ds, t0, t1, retries=3): |
| """拉一段时间的数据 (HAPI JSON).""" |
| url = (f"{HAPI}?id={ds}&time.min={t0}&time.max={t1}&format=json") |
| for attempt in range(retries): |
| try: |
| with urllib.request.urlopen(url, timeout=120) as r: |
| d = json.load(r) |
| code = d.get("status", {}).get("code") |
| if code == 1201: |
| return None |
| if code != 1200: |
| raise RuntimeError(f"HAPI status {code}: {d.get('status')}") |
| return d |
| except Exception as e: |
| if attempt == retries - 1: |
| print(f" [warn] {ds} {t0[:10]} 失败: {e}", flush=True) |
| return None |
| time.sleep(3 * (attempt + 1)) |
| return None |
|
|
|
|
| def download_month(ds_list, year, month, out_dir): |
| """下载一个月, 逐天下载后合并.""" |
| import numpy as np |
| if month == 12: |
| nxt = datetime(year + 1, 1, 1) |
| else: |
| nxt = datetime(year, month + 1, 1) |
| day = datetime(year, month, 1) |
|
|
| all_rows = {ds: [] for ds in ds_list} |
| ndays = 0 |
| while day < nxt: |
| d2 = day + timedelta(days=1) |
| t0 = day.strftime("%Y-%m-%dT%H:%M:%SZ") |
| t1 = d2.strftime("%Y-%m-%dT%H:%M:%SZ") |
| got = False |
| for ds in ds_list: |
| d = fetch(ds, t0, t1) |
| if d: |
| all_rows[ds].extend(d["data"]) |
| got = True |
| ndays += 1 if got else 0 |
| print(f" {t0[:10]} {'ok' if got else 'no-data'}", flush=True) |
| day = d2 |
|
|
| os.makedirs(out_dir, exist_ok=True) |
| out = os.path.join(out_dir, f"rbsp_a_{year}{month:02d}.npz") |
| save = {} |
| for ds in ds_list: |
| rows = all_rows[ds] |
| if not rows: |
| continue |
| times = [r[0] for r in rows] |
| vals = [] |
| for r in rows: |
| row = [] |
| for v in r[1:]: |
| if isinstance(v, list): |
| row.append(float("nan")) |
| elif v is None: |
| row.append(float("nan")) |
| else: |
| fv = float(v) |
| |
| if fv < -1e30: |
| fv = float("nan") |
| row.append(fv) |
| vals.append(row) |
| save[ds + "__time"] = np.array(times) |
| save[ds + "__vals"] = np.array(vals, dtype=np.float32) |
| np.savez_compressed(out, **save) |
| print(f"[save] {out} ({os.path.getsize(out)/1024:.0f} KB, {ndays} days)", flush=True) |
| return out |
|
|
|
|
| def main(): |
| ap = argparse.ArgumentParser() |
| ap.add_argument("--start", default="2015-01", help="起始月 YYYY-MM") |
| ap.add_argument("--months", type=int, default=3) |
| ap.add_argument("--out", default=OUT_DIR) |
| args = ap.parse_args() |
|
|
| y, m = map(int, args.start.split("-")) |
| ds_list = ["RBSP-A_DENSITY_EMFISIS-L4", |
| "RBSP-A_MAGNETOMETER_1SEC-GEI_EMFISIS-L3"] |
| for i in range(args.months): |
| yy, mm = y + (m - 1 + i) // 12, (m - 1 + i) % 12 + 1 |
| print(f"=== {yy}-{mm:02d} ===", flush=True) |
| download_month(ds_list, yy, mm, args.out) |
| print("done", flush=True) |
|
|
|
|
| if __name__ == "__main__": |
| main() |
|
|
