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Why can't decimal numbers be represented exactly in binary?
...le, the decimal number 0.1 doesn't have an exact binary representation, so it's dangerous to use the == operator to compare it to another floating-point number. I understand the principles behind floating-point representation.
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Can't connect to localhost on SQL Server Express 2012 / 2016
... to localhost. I tried localhost\SQLExpress and Windows authentication but it gives me an error message saying cannot connect. Am I missing something here? I've used SQL Server 2008 before and I've never had issues connecting to localhost. It seems that it can't even find it. Also in the Services I ...
What is an invariant?
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An invariant is more "conceptual" than a variable. In general, it's a property of the program state that is always true. A function or method that ensures that the invariant holds is said to maintain the invariant.
For instance, a binary search tree might have the invariant that for eve...
Understanding ibeacon distancing
Trying to grasp a basic concept of how distancing with ibeacon (beacon/ Bluetooth-lowenergy/BLE) can work. Is there any true documentation on how far exactly an ibeacon can measure. Lets say I am 300 feet away...is it possible for an ibeacon to detect this?
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Unable to find the wrapper “https” - did you forget to enable it when you configured PHP?
...'ll list out exactly everything I've done so far. I am running PHP 5.2.14 with Zend Debugging on the latest Eclipse version on my Windows XP computer. I have a 1 GB of RAM. I have XAMPP running with Apache, MySQL, and FileZilla installed.
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Xcode 4 hangs at “Attaching to (app name)”
...ode 4 and for some reason my app won't run in the simulator or iOS device. It was working perfectly in Xcode 3, but all of a sudden now when I press run the program stops at "Attaching to...". There doesn't seem to be any other info to help with this problem either.
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What is the strict aliasing rule?
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A typical situation where you encounter strict aliasing problems is when overlaying a struct (like a device/network msg) onto a buffer of the word size of your system (like a pointer to uint32_ts or uint16_ts). When you overlay a struct...
What is the significance of #pragma marks? Why do we need #pragma marks?
...to methods. They have no impact on the program at all.
For example, using it with Xcode 4 will make those items appear directly in the Jump Bar.
There is a special pragma mark - which creates a line.
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How should I ethically approach user password storage for later plaintext retrieval?
As I continue to build more and more websites and web applications I am often asked to store user's passwords in a way that they can be retrieved if/when the user has an issue (either to email a forgotten password link, walk them through over the phone, etc.) When I can I fight bitterly against thi...
How to order citations by appearance using BibTeX?
By default (using the plain style) BibTeX orders citations alphabetically.
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