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Count items by a derived key using lodash _.countBy
Details
Count items by a derived key from a collection.
Highlights:
_.countByExample:
[{"type":"a"},{"type":"b"},{"type":"a"}]type{"a":2,"b":1}Execution
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Tool usage guide
Count By is a high-performance utility that aggregates items within a JSON collection based on a specific key or property. Powered by the lodash _.countBy method, it allows you to quickly summarize data distributions and frequency counts without writing custom scripts.
Background
An analyst has a list of products and needs to know how many items are in each category.
Problem
Manually counting hundreds of items is prone to error.
How to use
Input the product array and set the iteratee to 'category'.
Collection: [{"id":1,"category":"electronics"},{"id":2,"category":"books"},{"id":3,"category":"electronics"}], Iteratee Type: Property/Path, Iteratee: categoryOutcome
{"electronics": 2, "books": 1}
Background
A developer is reviewing server logs to identify the distribution of response codes.
Problem
Need to quickly see how many 200, 404, and 500 errors occurred.
How to use
Paste the log array and count by the 'status' property.
Collection: [{"status":200},{"status":200},{"status":404}], Iteratee Type: Property/Path, Iteratee: statusThe tool accepts standard JSON arrays or JSON objects as input.
Identity counts the occurrences of the values themselves, while Property/Path counts occurrences based on a specific key found within the objects.
Yes, by selecting Property/Path, you can provide a dot-notation path to access nested values within your objects.
Yes, this tool utilizes the industry-standard lodash _.countBy function for reliable and consistent data processing.
The output is a JSON object where keys represent the unique values found and the values represent the count of those items.
Outcome
{"200": 2, "404": 1}