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How do I create a dictionary with keys from a list and values defaulting to (say) zero? [duplicate]
I have a = [1,2,3,4] and I want d = {1:0, 2:0, 3:0, 4:0}
5 Answers
5
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When should I use Struct vs. OpenStruct?
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180
With an OpenStruct, you can arbitrarily create attributes. A Struct, on the other hand, must ha...
Checking images for similarity with OpenCV
...ue (maybe a percentage) that indicates how similar these images are? E.g. 100% would be returned if the same image was passed twice, 0% would be returned if the images were totally different.
...
Get all attributes of an element using jQuery
...:
(function(old) {
$.fn.attr = function() {
if(arguments.length === 0) {
if(this.length === 0) {
return null;
}
var obj = {};
$.each(this[0].attributes, function() {
if(this.specified) {
obj[this.name] = this.value;
}
});
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How to add leading zeros?
...f digits to begin with, so let's try a harder example of making powers of 10 width 8 too.
anim <- 25499:25504
x <- 10 ^ (0:5)
paste (and it's variant paste0) are often the first string manipulation functions that you come across. They aren't really designed for manipulating numbers, but ...
Cost of exception handlers in Python
...e just tried the following:
import timeit
statements=["""\
try:
b = 10/a
except ZeroDivisionError:
pass""",
"""\
if a:
b = 10/a""",
"b = 10/a"]
for a in (1,0):
for s in statements:
t = timeit.Timer(stmt=s, setup='a={}'.format(a))
print("a = {}\n{}".format(a,s))
...
How do you add swap to an EC2 instance?
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10 Answers
10
Active
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How can I implode an array while skipping empty array items?
...ode('-', array_filter($array));
Obviously this will not work if you have 0 (or any other value that evaluates to false) in your array and you want to keep it. But then you can provide your own callback function.
share
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Rename specific column(s) in pandas
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30
A much faster implementation would be to use list-comprehension if you need to rename a single c...
Common MySQL fields and their appropriate data types
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answered Dec 10 '08 at 0:57
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