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Trim last character from a string
...- Removes all occurrences of
white space characters from the
beginning and end of this instance.
MSDN-Trim
Under this definition removing only last character from string is bad solution.
So if we want to "Trim last character from string" we should do something like this
Example as extens...
Running a command in a Grunt Task
I'm using Grunt (task-based command line build tool for JavaScript projects) in my project. I've created a custom tag and I am wondering if it is possible to run a command into it.
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Command line progress bar in Java
I have a Java program running in command line mode.
I would like to display a progress bar, showing the percentage of job done.
The same kind of progress bar you would see using wget under unix.
Is this possible?
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“Insert if not exists” statement in SQLite
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If you have a table called memos that has two columns id and text you should be able to do like this:
INSERT INTO memos(id,text)
SELECT 5, 'text to insert'
WHERE NOT EXISTS(SELECT 1 FROM memos WHERE id = 5 AND text = 'text to insert');
If a record already contains a row where ...
dplyr: “Error in n(): function should not be called directly”
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I presume you have dplyr and plyr loaded in the same session. dplyr is not plyr. ddply is not a function in the dplyr package.
Both dplyr and plyr have the functions summarise/summarize.
Look at the results of conflicts() to see masked objects.
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Integer division: How do you produce a double?
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@FabricioPH This works in every situation, and identically to the *1.0 solution.
– Vitruvius
Feb 23 '14 at 7:55
3
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Add a default value to a column through a migration
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I tried it on PostgreSQL and it updated previously created fields.
– Aboozar Rajabi
May 12 '16 at 6:31
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Get User's Current Location / Coordinates
How can I store the user's current location and also show the location on a map?
15 Answers
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How do I get around type erasure on Scala? Or, why can't I get the type parameter of my collections?
... you instantiate a List[Int], you can verify that your instance is a List, and you can verify that any individual element of it is an Int, but not that it is a List[Int], as can be easily verified:
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How update the _id of one MongoDB Document?
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You cannot update it. You'll have to save the document using a new _id, and then remove the old document.
// store the document in a variable
doc = db.clients.findOne({_id: ObjectId("4cc45467c55f4d2d2a000002")})
// set a new _id on the document
doc._id = ObjectId("4c8a331bda76c559ef000004")
//...