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How do I merge two dictionaries in a single expression in Python (taking union of dictionaries)?
...tionaries 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() # start with x's ...
Split a string by a delimiter in python
...
@EndenDragon The for loop will automatically apply x.strip() and return a list of matches without whitespace on either side. The devil is in the details.
– Sébastien Vercammen
Jun 29 '16 at 13:59
...
Image Greyscale with CSS & re-color on mouse-over?
...rayscale(100%);
/* Chrome 19+ & Safari 6+ */
-webkit-transition: all .6s ease;
/* Fade to color for Chrome and Safari */
-webkit-backface-visibility: hidden;
/* Fix for transition flickering */
}
img.grayscale:hover {
filter: none;
-webkit-filter: grayscale(0%);
}
sv...
Retrieve only the queried element in an object array in MongoDB collection
...r to filter an array during projection, which has the benefit of including all matches, instead of just the first one.
db.test.aggregate([
// Get just the docs that contain a shapes element where color is 'red'
{$match: {'shapes.color': 'red'}},
{$project: {
shapes: {$filter: {
...
How to define a two-dimensional array?
...
You're technically trying to index an uninitialized array. You have to first initialize the outer list with lists before adding items; Python calls this
"list comprehension".
# Creates a list containing 5 lists, each of 8 items, all set t...
When to encode space to plus (+) or %20?
...value is query value with a space, but the folder name in the path is literally foo+bar, not foo bar.
%20 is a valid way to encode a space in either of these contexts. So if you need to URL-encode a string for inclusion in part of a URL, it is always safe to replace spaces with %20 and pluses with ...
Android Center text on canvas
... at the center position: int xPos = (Width - textPaint.TextSize * Math.Abs(_text.Length / 2)) / 2; Not sure if there's a better way to accomplish this.
– paj7777
Apr 8 '13 at 9:06
...
split string only on first instance - java
... length will be no greater than n, and the array's last entry will contain all input beyond the last matched delimiter.
The string boo:and:foo, for example, yields the following results with these parameters:
Regex Limit Result
: 2 { "boo", "and:foo" }
: 5 { "boo", "an...
Changing the cursor in WPF sometimes works, sometimes doesn't
...deCursor:
Mouse.OverrideCursor = Cursors.Wait;
try
{
// do stuff
}
finally
{
Mouse.OverrideCursor = null;
}
This overrides the cursor for your application rather than just for a part of its UI, so the problem you're describing goes away.
...
How to remove multiple indexes from a list at the same time? [duplicate]
...t-in operation to remove a number of indexes at once.
Your example is actually a contiguous sequence of indexes, so you can do this:
del my_list[2:6]
which removes the slice starting at 2 and ending just before 6.
It isn't clear from your question whether in general you need to remove an arbitr...