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$弧度 ToDegrees
8.0.1 版中的新增内容。
Amazon DocumentDB 中的$radiansToDegrees运算符将值从弧度转换为度。
参数
示例（MongoDB Shell）
以下示例显示如何使用$radiansToDegrees运算符将弧度值转换为度。
创建示例文档
db.angles.insertMany([
{ "_id": 1, "radians": 0 },
{ "_id": 2, "radians": 1.5707963267948966 },
{ "_id": 3, "radians": 3.141592653589793 },
{ "_id": 4, "radians": 6.283185307179586 }
]);
查询示例
db.angles.aggregate([
{ $project: {
"degrees": { $radiansToDegrees: "$radians" }
}}
]);
输出
[
{ "_id": 1, "degrees": 0 },
{ "_id": 2, "degrees": 90 },
{ "_id": 3, "degrees": 180 },
{ "_id": 4, "degrees": 360 }
]
代码示例
要查看使用$radiansToDegrees运算符的代码示例，请选择要使用的语言的选项卡：
- Node.js
-
const { MongoClient } = require('mongodb');
async function main() {
const client = await MongoClient.connect('mongodb://<username>:<password>@<cluster-endpoint>:27017/?tls=true&tlsCAFile=global-bundle.pem&replicaSet=rs0&readPreference=secondaryPreferred&retryWrites=false');
const db = client.db('test');
const collection = db.collection('angles');
const result = await collection.aggregate([
{ $project: {
"degrees": { $radiansToDegrees: "$radians" }
}}
]).toArray();
console.log(result);
await client.close();
}
main();
- Python
-
from pymongo import MongoClient
def main():
client = MongoClient('mongodb://<username>:<password>@<cluster-endpoint>:27017/?tls=true&tlsCAFile=global-bundle.pem&replicaSet=rs0&readPreference=secondaryPreferred&retryWrites=false')
db = client['test']
collection = db['angles']
result = list(collection.aggregate([
{ '$project': {
'degrees': { '$radiansToDegrees': '$radians' }
}}
]))
print(result)
client.close()
if __name__ == "__main__":
main()
