Introduction to MongoDB $sinh Operator
$sinh
is a mathematical operator in MongoDB used to calculate the hyperbolic sine value of a given angle. It accepts an angle value in radians and returns its hyperbolic sine value. The operator is calculated as sinh(x) = (e^x - e^{-x})/2
, where e is the base of the natural logarithm.
Syntax
The syntax of the $sinh
operator is as follows:
{ $sinh: <angle> }
where <angle>
is an angle value in radians.
Use Cases
The $sinh
operator is commonly used in scenarios where the hyperbolic sine value of data needs to be calculated, such as in scientific, engineering, and statistical analysis fields. It can be used for preprocessing data and can be used in conjunction with other operators in the aggregation pipeline.
Example
Suppose we have a collection named students
that contains the name and score of students, and we want to convert the score of each student to its hyperbolic sine value and store the transformed value as a new field sinh_score
in the document. We can use the following aggregation pipeline to achieve this:
db.students.aggregate([
{
$project: {
name: 1,
score: 1,
sinh_score: { $sinh: { $toRadians: "$score" } }
}
}
])
In the above aggregation pipeline, we first use the $project
operator to select the fields to be retained and convert the score to radians. Then, we use the $sinh
operator to calculate the hyperbolic sine value of each student’s score and store it in the new field sinh_score
.
Suppose our students
collection has the following documents:
{ "_id": 1, "name": "Alice", "score": 45 }
{ "_id": 2, "name": "Bob", "score": 60 }
{ "_id": 3, "name": "Charlie", "score": 75 }
After running the above aggregation pipeline, we get the following output:
{ "_id": 1, "name": "Alice", "score": 45, "sinh_score": 1.4220556639764496 }
{ "_id": 2, "name": "Bob", "score": 60, "sinh_score": 0.5781976143544594 }
{ "_id": 3, "name": "Charlie", "score": 75, "sinh_score": 0.10126251903445213 }
We can see that a new field named sinh_score
has been added to each document, which stores the hyperbolic sine value of each student’s score.
Conclusion
The $sinh
operator is a commonly used mathematical operator in MongoDB used to calculate the hyperbolic sine value of a given number. Its syntax is straightforward, requiring only the use of the $sinh
keyword in the aggregation expression. The operator is commonly used in handling large amounts of numerical data, such as in data analysis and statistical applications.
When using the $sinh
operator, it is important to note the matching of data types. Passing non-numeric parameters can result in calculation errors or errors. In addition, for a large amount of data calculations, it is also important to pay attention to the efficiency and performance of the operation, which can be improved by reasonable indexing and query optimization.
Overall, the $sinh
operator is a convenient and practical mathematical function that can be used for data processing and analysis in the aggregation pipeline. In practical applications, it is necessary to choose and use based on specific scenarios and data types.