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getMinutes() 0-9 - How to display two digit numbers?
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(condition?true:false) in PHP you can omit the true statement (condition?:false) in JS you would then use (condition||false) Ternary operator en.wikipedia.org/wiki/Ternary_operation
– llange
Mar 16 '19 at 9:53
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NoSQL (MongoDB) vs Lucene (or Solr) as your database
...tially update a document in solr. You have to re-post all of the fields in order to update a document.
And performance matters. If you do not commit, your change to solr does not take effect, if you commit every time, performance suffers.
There is no transaction in solr.
As solr has these disadvanta...
How to pass a function as a parameter in Java? [duplicate]
...t of this post describes what we used to have to do in the bad old days in order to implement this functionality.
Typically you declare your method as taking some interface with a single method, then you pass in an object that implements that interface. An example is in commons-collections, where y...
How to compare objects by multiple fields
...thenComparing(Person::getLastName, Comparator.nullsFirst(Comparator.naturalOrder())) - first field selector, then comparator
– gavenkoa
May 30 '18 at 14:22
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How can I reverse the order of lines in a file?
I'd like to reverse the order of lines in a text file (or stdin), preserving the contents of each line.
25 Answers
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The smallest difference between 2 Angles
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It returns the signed delta angle. Note that depending on your API the order of the parameters for the atan2() function might be different.
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Asynchronous vs synchronous execution, what does it really mean? [closed]
...nd you.
ASYNCHRONOUS
You are in a restaurant with many other people. You order your food. Other people can also order their food, they don't have to wait for your food to be cooked and served to you before they can order.
In the kitchen restaurant workers are continuously cooking, serving, and tak...
How does one reorder columns in a data frame?
...s keep all the rows, and the 1,2,3,4 refers to the columns.
To change the order as in the above question do df2[,c(1,3,2,4)]
If you want to output this file as a csv, do write.csv(df2, file="somedf.csv")
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How to sort an ArrayList?
... have a List of doubles in java and I want to sort ArrayList in descending order.
20 Answers
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How should one use std::optional?
...lacement new and a lot more other things with proper alignment and size in order to make it a literal type (i.e. use with constexpr) among other things. The naive T and bool approach would fail pretty quickly.
– Rapptz
Mar 13 '14 at 22:05
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