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Why doesn't this code simply print letters A to Z?
...metic operations on character variables and not C's.
For example, in Perl 'Z'+1 turns into 'AA', while in C 'Z'+1 turns into '[' ( ord('Z') == 90, ord('[') == 91 ).
Note that character variables can be incremented but not decremented and even so only plain ASCII characters (a-z and A-Z) are supporte...
Java regex email
...static final Pattern VALID_EMAIL_ADDRESS_REGEX =
Pattern.compile("^[A-Z0-9._%+-]+@[A-Z0-9.-]+\\.[A-Z]{2,6}$", Pattern.CASE_INSENSITIVE);
public static boolean validate(String emailStr) {
Matcher matcher = VALID_EMAIL_ADDRESS_REGEX.matcher(emailStr);
return matcher.find();
}
W...
Why does z-index not work?
So if I understand z-index correctly, it would be perfect in this situation:
4 Answers
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css z-index lost after webkit transform translate3d
I have two absolutely positioned div elements that overlap. Both have set z-index values via css. I use the translate3d webkit transform to animate these elements off the screen, and then back onto the screen. After the transform, the elements no longer respect their set z-index values.
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z-index not working with fixed positioning
...ent in this case)
Positioned elements (and their children) with negative z-index values (higher values are stacked in front of lower values; elements with the same value are stacked according to appearance in the HTML)
Non-positioned elements (ordered by appearance in the HTML)
Positioned elem...
Preserving signatures of decorated functions
... convert all arguments to a specific type, perform logging, implement memoization, etc.
6 Answers
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How do I merge two dictionaries in a single expression in Python (taking union of dictionaries)?
...two Python dictionaries in a single expression?
For dictionaries x and y, z becomes a shallowly merged dictionary with values from y replacing those from x.
In Python 3.5 or greater:
z = {**x, **y}
In Python 2, (or 3.4 or lower) write a function:
def merge_two_dicts(x, y):
z = x.copy() # s...
How to sort a dataframe by multiple column(s)
...ns. For example, with the data.frame below I would like to sort by column z (descending) then by column b (ascending):
...
Defining an array of anonymous objects in CoffeeScript
... island205island205
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How to count TRUE values in a logical vector
...re some problems when logical vector contains NA values.
See for example:
z <- c(TRUE, FALSE, NA)
sum(z) # gives you NA
table(z)["TRUE"] # gives you 1
length(z[z == TRUE]) # f3lix answer, gives you 2 (because NA indexing returns values)
So I think the safest is to use na.rm = TRUE:
sum(z, na....