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How can I check if a string represents an int, without using try/except?
...er a string represents an integer (e.g., '3' , '-17' but not '3.14' or 'asfasfas' ) Without using a try/except mechanism?
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When is CRC more appropriate to use than MD5/SHA1?
When is it appropriate to use CRC for error detection versus more modern hashing functions such as MD5 or SHA1? Is the former easier to implement on embedded hardware?
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recursion versus iteration
Is it correct to say that everywhere recursion is used a for loop could be used? And if recursion is usually slower what is the technical reason for ever using it over for loop iteration?
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Align items in a stack panel?
I was wondering if I can have 2 controls in a horizontal-oriented StackPanel so that the right item should be docked to the right side of the StackPanel.
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iPhone system font
...of font purists
everywhere, the iPhone system
interface uses Helvetica or a variant
thereof.
The original iPhone, iPhone 3G and
iPhone 3GS system interface uses
Helvetica. As first noted by the
always excellent DaringFireball, the
iPhone 4 uses a subtly revised font
called "Helv...
OnChange event handler for radio button (INPUT type=“radio”) doesn't work as one value
I'm looking for a generalized solution for this.
16 Answers
16
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What does %w(array) mean?
I'm looking at the documentation for FileUtils.
8 Answers
8
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What does the property “Nonatomic” mean?
...e Apple Docs.
Basically, if you say nonatomic, and you generate the accessors using @synthesize, then if multiple threads try to change/read the property at once, badness can happen. You can get partially-written values or over-released/retained objects, which can easily lead to crashes. (This is p...
How to get 0-padded binary representation of an integer in java?
for example, for 1, 2, 128, 256 the output can be (16 digits):
17 Answers
17
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Combine two columns of text in pandas dataframe
...tenate them directly:
df["period"] = df["Year"] + df["quarter"]
If one (or both) of the columns are not string typed, you should convert it (them) first,
df["period"] = df["Year"].astype(str) + df["quarter"]
Beware of NaNs when doing this!
If you need to join multiple string columns, you ca...