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Understanding ibeacon distancing
...t 1 meter away. Each beacon must be calibrated with this txPower value to allow accurate distance estimates.
While the distance estimates are useful, they are not perfect, and require that you control for other variables. Be sure you read up on the complexities and limitations before misusing thi...
Lambda function in list comprehensions
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The first one creates a single lambda function and calls it ten times.
The second one doesn't call the function. It creates 10 different lambda functions. It puts all of those in a list. To make it equivalent to the first you need:
[(lambda x: x*x)(x) for x in range(10)]
Or b...
Error java.lang.OutOfMemoryError: GC overhead limit exceeded
...garbage collector is taking an excessive amount of time (by default 98% of all CPU time of the process) and recovers very little memory in each run (by default 2% of the heap).
This effectively means that your program stops doing any progress and is busy running only the garbage collection at all t...
Why does viewWillAppear not get called when an app comes back from the background?
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In other words, if someone looks at another application or takes a phone call, then switches back to your app which was earlier on backgrounded, your UIViewController which was already visible when you left your app 'doesn't care' so to speak -- as far as it is concerned, it's never disappeared and...
What is Weak Head Normal Form?
... further (i.e. it contains no un-evaluated thunks).
These expressions are all in normal form:
42
(2, "hello")
\x -> (x + 1)
These expressions are not in normal form:
1 + 2 -- we could evaluate this to 3
(\x -> x + 1) 2 -- we could apply the function
"he" ++ "llo" ...
Programmatically fire button click event?
Is there a way to programmatically fire a button click event? I have a button placed there in an UIView, and in a particular scenario i want to click the button via code, not manually as a user. Is it possible in iOS development? Please provide your suggestions and guide me how to do that.
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How to check if bootstrap modal is open, so i can use jquery validate
i need to make a validation only if a modal is open, because if i open it, and then i close it, and the i press the button that opens the modal it doesn't work because it is making the jquery validation, but not showing because the modal was dismissed.
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Postgres - FATAL: database files are incompatible with server
...an run the below command to upgrade your postgres data directory retaining all data:
brew postgresql-upgrade-database
The above command is taken from the output of brew info postgres
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Difference between Convert.ToString() and .ToString()
What is the difference between Convert.ToString() and .ToString() ?
19 Answers
19
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How to export all data from table to an insertable sql format?
I have a Table (call it A_table ) in a database (call it A_db ) in Microsoft SQL Server Management Studio, and there are 10 rows.
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