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Finding all possible combinations of numbers to reach a given sum
How would you go about testing all possible combinations of additions from a given set N of numbers so they add up to a given final number?
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What's the difference between django OneToOneField and ForeignKey?
...Guide to Django:
OneToOneField
A one-to-one relationship. Conceptually, this is similar to a ForeignKey with unique=True, but the "reverse" side of the relation will directly return a single object.
In contrast to the OneToOneField "reverse" relation, a ForeignKey "reverse" relation retur...
What is in your Mathematica tool bag? [closed]
We all know that Mathematica is great, but it also often lacks critical functionality. What kind of external packages / tools / resources do you use with Mathematica?
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How to send a command to all panes in tmux?
I like to call :clear-history on panes with a huge scrollback. However, I want to script a way to send this command to all the panes in the various windows.
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Transpose/Unzip Function (inverse of zip)?
...'d', 4)])
[('a', 'b', 'c', 'd'), (1, 2, 3, 4)]
The way this works is by calling zip with the arguments:
zip(('a', 1), ('b', 2), ('c', 3), ('d', 4))
… except the arguments are passed to zip directly (after being converted to a tuple), so there's no need to worry about the number of arguments g...
How to wait for several Futures?
...ave several futures and need to wait until either any of them fails or all of them succeed.
8 Answers
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Include all existing fields and add new fields to document
...t aggregation stage where I can instruct it to add a new field and include all existing fields, without having to list all the existing fields.
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What is the difference between save and insert in Mongo DB?
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Save Vs Insert :
In your given examples, the behavior is essentially the same.
save behaves differently if it is passed with an "_id" parameter.
For save, If the document contains _id, it will upsert querying the collection on the _id field, If not, it will insert.
If a document does not...
Passing argument to alias in bash [duplicate]
...etom: If you're referring to the colors in my answer, that's done automatically by the syntax highlighter.
– Paused until further notice.
Jul 7 '14 at 5:12
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To underscore or to not to underscore, that is the question
...other framework languages? For example since C# is case-sensitive you can call a field "foo" and the public property "Foo" and it works fine.
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