NEWS

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vayuayan 0.3.0

Breaking changes

• CPCB station lists come from a bundled directory and work offline.
• Live AQI holds only the latest hour: date, hour and date_time are ignored with a warning; last_hours is removed.
• pm25_download_netcdf() fetches V6.GL.03 (1998-2024) from the AWS satpmdata bucket; the v6.gl.02.04 bucket is gone.
• Downloads are cached in vayuayan_cache_dir(); files in the Python package's cache are reused.
• pm25_v5gl04_monthly() is now pm25_monthly(version = "V5GL04").
• cpcb_get_file_path() returns CPCB's entries as sent: filepath (was filePath) and year as CPCB gives it.

New features

• theme_vayuayan() (the ggplot2 theme of the package's figures) and plot_sensor_vs_reference().
• compute_us_aqi(), us_aqi_sub_index(), us_aqi_category(), us_aqi_color() and us_aqi_pollutant_name() calculate the US EPA AQI with the May 2024 EPA tables. Labels with a mass unit, such as "O3 (ug/m3)", are converted to ppm or ppb at 25 degrees C.
• CPCB National AQI: compute_aqi(), aqi_sub_index(), daily_aqi(). Above the Severe band the sub-index continues on the same slope, as in CPCB's AQI calculator, and the AQI is rounded half up.
• Raw and hourly CPCB data: cpcb_download_raw_station_data(), cpcb_download_hourly_city_data(), cpcb_download_hourly_station_data(), cpcb_raw_to_long(), cpcb_station_daily_aqi().
• Daily data in long form: cpcb_tidy_daily(), cpcb_city_daily(), cpcb_station_daily().
• Stations can be given by name or a unique part of it ("Anand Vihar, Delhi"), not just ID.
• cpcb_get_nearest_stations() and stations_to_city_summary().
• PM2.5 functions take version ("V6GL03", "V6", "V5", "V5GL04") and region ("AS" for the smaller Asia files).
• pm25_get_point(), pm25_get_stats_by_polygon(), pm25_monthly().
• india_boundary() and pm25_map().
• oaq_stations_table(); oaq_fetch_monthly_stations() takes several providers.
• OAQ sensor tools: oaq_sensors(), oaq_readings(), oaq_daily_means(), oaq_daily_records(), oaq_check_daily_records(), oaq_nearest_cpcb(), oaq_city_tally(); cpcb_raw_readings() for several stations.
• OAQ daily records: compare_daily_records(), daily_record_summary(), oaq_audit_daily_records() and the plot_daily_record_*() figures (ggplot2).
• Sensor quality checks against the US EPA targets for PM2.5 sensors: readings_mean(), sensor_completeness(), sensor_plausibility(), collocated_precision(), peer_ratio(), sensor_accuracy(), ratio_by_humidity().
• aqi_health_impact(), aqi_pollutant_category(), cpcb_live_to_long() and cpcb_live_metrics().

Bug fixes

• OAQ responses with bare NaN values (some daily files of 2025) are read with NA; before, oaq_readings() and the functions that use it left those days out.
• oaq_fetch_monthly_stations() failed when providers return different columns or id types; oaq_get_city_latest() needs a lower-case city in OAQ's paths and now lower-cases it; OAQ data requests are retried after network errors and 5xx statuses. The OAQ examples use real sensors.
• get_aqi_categories() returns character(0) for empty input.
• analyze_station_data() counted columns instead of cities.
• Interrupted PM2.5 downloads no longer leave partial files in the cache.

Other changes

• Dropped geosphere, glue and lubridate, and the startup message.
• Station, state and city lists sort in C-locale order; cities of the live feed sort by share of live stations, then name. Hourly readings are numeric. PM2.5 std divides by n (population standard deviation of the grid cells).
• Analysis vignettes moved to pkgdown articles.