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“Cannot connect to iTunes Store” in-app purchases
I am having problems testing my in-app purchases. I get back valid product identifiers, but upon purchase I receive the dreaded "Cannot connect to iTunes Store". Interesting thing is that restore purchases seems to work - iTunes login pops up.
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What is a magic number, and why is it bad? [closed]
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A magic number is a direct usage of a number in the code.
For example, if you have (in Java):
public class Foo {
public void setPassword(String password) {
// don't do this
if (password.length() > 7) {
throw new InvalidArgumentEx...
What is the difference between concurrency and parallelism?
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Concurrency is when two or more tasks can start, run, and complete in overlapping time periods. It doesn't necessarily mean they'll ever both be running at the same instant. For example, multitasking on a single-core machine.
Parallelism is when tasks literally run at the same time, e.g.,...
What is in your Mathematica tool bag? [closed]
...athematica is great, but it also often lacks critical functionality. What kind of external packages / tools / resources do you use with Mathematica?
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What is an “unwrapped value” in Swift?
I'm learning Swift for iOS 8 / OSX 10.10 by following this tutorial , and the term " unwrapped value " is used several times, as in this paragraph (under Objects and Class ):
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How bad is shadowing names defined in outer scopes?
I just switched to Pycharm and I am very happy about all the warnings and hints it provides me to improve my code. Except for this one which I don't understand:
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How to iterate a loop with index and element in Swift
Is there a function that I can use to iterate over an array and have both index and element, like Python's enumerate ?
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How to document class attributes in Python? [closed]
I'm writing a lightweight class whose attributes are intended to be publicly accessible, and only sometimes overridden in specific instantiations. There's no provision in the Python language for creating docstrings for class attributes, or any sort of attributes, for that matter. What is the expec...
n-grams in python, four, five, six grams?
I'm looking for a way to split a text into n-grams.
Normally I would do something like:
15 Answers
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How to delete multiple values from a vector?
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The %in% operator tells you which elements are among the numers to remove:
> a <- sample (1 : 10)
> remove <- c (2, 3, 5)
> a
[1] 10 5 2 7 1 6 3 4 8 9
> a %in% remove
[1] FALSE TRUE TRUE FALSE FALSE...