Using numpy to build an array of all combinations of two arrays
Cartesian product function by Stackoverflow user, pv.
See Answer here.
zchking
/ README.md
Created
July 16, 2019 10:03
— forked from hernamesbarbara/README.md
A numpy implementation ~5× faster than using itertools.
zchking
/ mongodb_distinct_count.js
Last active
August 5, 2020 02:50
— forked from clarkenheim/mongodb_distinct_count.js
MongoDB equivalent of an SQL query to get the distinct values of a field in a collection including the count of documents which have each distinct value (distinct with count)
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| //equivalent of MySQL SELECT COUNT(*) AS cnt, fieldName FROM someTable GROUP BY fieldName; | |
| db.someCollection.aggregate([{"$group" : {_id:"$fieldName", cnt:{$sum:1}}}]); | |
| //as above but ordered by the count descending | |
| //eg: SELECT COUNT(*) AS cnt, fieldName FROM someTable GROUP BY fieldName ORDER BY cnt DESC; | |
| db.someCollection.aggregate([{"$group" : {_id:"$fieldName", cnt:{$sum:1}}}, {$sort:{'cnt':-1}}]); | |
| db.order.aggregate([{ $group: { _id: "$seller_email", total_order: { "$sum": 1 }, | |
| seller_address_1 : { $first: '$seller_address_1' }, | |
| seller_country : { $first: '$seller_country' }, |