颱風來了，在做好防颱準備之後，我們用颱風警報的資訊做練習吧!

• 下圖是預計要的結果:
  

• 資料的來源是 https://opendata.cwa.gov.tw/ 的 颱風消息與警報-熱帶氣旋路徑，使用資料會需要註冊，並取得授權碼喔!

觀察資料

透過資料來源的說明，可以知道取得的資料裡面會有 analysis_data: 過去及現在熱帶氣旋位置。

• STEP1: 取得 json 資料，本地練習使用

curl -s https://opendata.cwa.gov.tw/api/v1/rest/datastore/W-C0034-005?Authorization=${你的授權碼} > typhoon0930.json

• STEP2: 使用 keys 看看資料

jq "keys" typhoon0930.json

• STEP3: 往下找好幾層，終於看到 analysis_data

• STEP4: 似乎有兩個 analysis_data，透過名字來看看該看哪一個吧。

jq ".records.tropicalCyclones.tropicalCyclone[] | {typhoonName, cwaTyphoonName}" typhoon0930
.json

篩選資料、一邊篩選一邊觀察

• STEP5: 鎖定 山陀兒 颱風 select(.typhoonName==\"KRATHON\")，底下的 .analysisData.fix 陣列裡面，目前有 34 筆資料。

jq ".records.tropicalCyclones.tropicalCyclone[] | select(.typhoonName==\"KRATHON\") | .analysisData.fix | length" typhoon0930.json

34

• STEP6: .analysisData.fix 陣列裡面一個元素有以下屬性名稱

jq -c ".records.tropicalCyclones.tropicalCyclone[] | select(.typhoonName==\"KRATHON\") | .analysisData.fix[0] | keys_unsorted" typhoon0930.json

["fixTime","coordinate","maxWindSpeed","maxGustSpeed","pressure","movingSpeed","movingDirection","movingPrediction"]

• STEP7: 觀察最後一個元素

jq -c ".records.tropicalCyclones.tropicalCyclone[] | select(.typhoonName==\"KRATHON\") | .analysisData.fix[-1] " typhoon0930.json

{"fixTime":"2024-09-30T20:00:00+08:00","coordinate":"120.5,20.5","maxWindSpeed":"48","maxGustSpeed":"58","pressure":"930","movingSpeed":"10","movingDirection":"W","movingPrediction":[{"value":"以每小時6公里速度，向西北西轉北進行","lang":"zh-hant"},{"value":"WNW TURNING NORTH 6 KM/HR","lang":"en-us"}],"circleOf15Ms":{"radius":"200","quadrantRadii":{"radius":[{"value":"190","dir":"NE"},{"value":"200","dir":"SE"},{"value":"200","dir":"SW"},{"value":"200","dir":"NW"}]}},"circleOf25Ms":{"radius":"70","quadrantRadii":{"radius":[{"value":"190","dir":"NE"},{"value":"200","dir":"SE"},{"value":"200","dir":"SW"},{"value":"200","dir":"NW"}]}}}

選擇要看的資料屬性

• STEP8: 選擇要看的資料屬性，每一筆資料要用陣列呈現

jq -c "[.records.tropicalCyclones.tropicalCyclone[] | select(.typhoonName==\"KRATHON\") | .analysisData.fix[-1] | .fixTime, .movingDirection, .coordinate, .pressure, .maxWindSpeed, .maxGustSpeed, .moving
Prediction[0].value] " typhoon0930.json

["2024-09-30T20:00:00+08:00","W","120.5,20.5","930","48","58","以每小時6公里速度，向西北西轉北進行"]

• STEP9: 取得所有內容

jq -c "[.records.tropicalCyclones.tropicalCyclone[] | select(.typhoonName==\"KRATHON\") | .analysisData.fix[] | [.fixTime, .movingDirection, .coordinate, .pressure, .maxWindSpeed, .maxGustSpeed, .movingPrediction[0].value]][] " typhoon0930.json

["2024-09-30T02:00:00+08:00","WNW","122.5,19.8","945","43","53",null]
["2024-09-30T03:00:00+08:00","W","122.4,19.8","945","43","53",null]
["2024-09-30T04:00:00+08:00","N","122.4,19.9","945","43","53",null]
["2024-09-30T05:00:00+08:00","W","122.3,19.9","945","43","53",null]
["2024-09-30T06:00:00+08:00","W","122.2,19.9","945","43","53",null]
["2024-09-30T07:00:00+08:00","N","122.2,20.0","945","43","53",null]
["2024-09-30T08:00:00+08:00","W","122.1,20.0","940","45","55",null]
["2024-09-30T09:00:00+08:00","NNW","122.0,20.2","940","45","55",null]
["2024-09-30T10:00:00+08:00","W","121.9,20.2","940","45","55",null]
["2024-09-30T11:00:00+08:00","W","121.8,20.2","940","45","55",null]
["2024-09-30T12:00:00+08:00","NW","121.6,20.4","940","45","55",null]
["2024-09-30T13:00:00+08:00","W","121.5,20.4","940","45","55",null]
["2024-09-30T14:00:00+08:00","NW","121.4,20.5","940","45","55",null]
["2024-09-30T15:00:00+08:00","W","121.2,20.5","940","45","55",null]
["2024-09-30T16:00:00+08:00","W","121.0,20.5","940","45","55",null]
["2024-09-30T17:00:00+08:00","W","120.8,20.5","940","45","55",null]
["2024-09-30T18:00:00+08:00","W","120.7,20.5","940","45","55",null]
["2024-09-30T19:00:00+08:00","W","120.6,20.5","940","45","55",null]
["2024-09-30T20:00:00+08:00","W","120.5,20.5","930","48","58","以每小時6公里速度，向西北西轉北進行"]

結論

今天練習到這邊，已經拿到足夠追蹤颱風消息的資料了~ 不知道認真學習的各位，有沒有順利拿到想看的資料了呢?有沒有信心? 😊 有沒有成就感? 😊

其他呈現和輸出部分，明天後天再繼續學習吧! 做好防颱準備~ GO !