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Getting the array length of a 2D array in Java
I need to get the length of a 2D array for both the row and column. I’ve successfully done this, using the following code:
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The differences between .build, .create, and .create! and when should they be used?
So I've been seeing people using .build , .create , and .create! within their controllers more and more lately. What's the difference from just using .new and passing the param'd object and then .save ? Are there pros and cons? Does using these other methods offer benefits?
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The model backing the context has changed since the database was created
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I've changed my production db manually and turned off the migration and it works, Thanks
– Mohsen Afshin
Sep 10 '12 at 21:05
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Error: “dictionary update sequence element #0 has length 1; 2 is required” on Django 1.4
...nts to parse the given positional argument as the keyword argument kwargs, and since a string is an iterable, an atypical code path begins to unfold. Always use name= on your urls!
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How to exit from Python without traceback?
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You are presumably encountering an exception and the program is exiting because of this (with a traceback). The first thing to do therefore is to catch that exception, before exiting cleanly (maybe with a message, example given).
Try something like this in your main r...
How do detect Android Tablets in general. Useragent?
...sing a Motorola Zoom to try our tablet site testing.
The issue is that the Android Useragent is a general Useragent and there is no difference between tablet Android and mobile Android. I don't want to just target a specific device like the Xoom Useragent since Android will most likely be on multip...
Should switch statements always contain a default clause?
...pe! based on the language,
// there should probably be some error-handling
// here, maybe an exception
}
2. To handle 'default' actions, where the cases are for special behavior.
You see this a LOT in menu-driven programs and bash shell scripts. You might also see this when a vari...
Where is the “Fold” LINQ Extension Method?
... prod * next);
See MSDN for more information. It lets you specify a seed and then an expression to calculate successive values.
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Counting the number of elements with the values of x in a vector
... x creates a logical vector which is TRUE at every location that x occurs, and when suming, the logical vector is coerced to numeric which converts TRUE to 1 and FALSE to 0.
However, note that for floating point numbers it's better to use something like: sum(abs(numbers - x) < 1e-6).
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Is the != check thread safe?
... edited Apr 15 '16 at 12:57
Andrew Tobilko
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answered Aug 27 '13 at 8:35
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