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Check if a given key already exists in a dictionary
...e intended way to test for the existence of a key in a dict.
d = {"key1": 10, "key2": 23}
if "key1" in d:
print("this will execute")
if "nonexistent key" in d:
print("this will not")
If you wanted a default, you can always use dict.get():
d = dict()
for i in range(100):
key = i % ...
Checking that a List is not empty in Hamcrest
...
answered Sep 2 '10 at 20:47
skaffmanskaffman
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Cancel a UIView animation?
...n DarlingtonStephen Darlington
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How to deep copy a list?
...], [4, 5, 6]]
>>> b
[[1, 2, 3], [4, 5, 6]]
>>> a[0][1] = 10
>>> a
[[1, 10, 3], [4, 5, 6]]
>>> b # b changes too -> Not a deepcopy.
[[1, 10, 3], [4, 5, 6]]
Now see the deepcopy operation
>>> import copy
>>> b = copy.deepcopy(a)
>>>...
Convert data.frame column format from character to factor
...cols.to.factor <- sapply( df, function(col) length(unique(col)) < log10(length(col)) )
df[ cols.to.factor] <- lapply(df[ cols.to.factor] , factor)
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“tag already exists in the remote" error after recreating the git tag
...eir "wrong tag" and replace it with the new "right tag".
Testing in Git 2.10/2.11 shows that retaining the old tag is the default behavior for clients running git fetch, and updating is the default behavior for clients running git fetch --tags.
(Original answer follows.)
When you ask to push ta...
How to get the ThreadPoolExecutor to increase threads to max before queueing?
...also define it as a bounded queue. For example, if you add a capacity of 1000 to the LinkedBlockingQueue then it will:
scale the threads up to max
then queue up until it is full with 1000 tasks
then block the caller until space becomes available to the queue.
Also, if you needed to use offer(....
How to get the current directory in a C program?
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edited Jun 4 '12 at 10:59
Aurelio De Rosa
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an...
Count number of matches of a regex in Javascript
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edited Apr 10 '18 at 20:52
Trevor
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Cast Double to Integer in Java
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hvgotcodeshvgotcodes
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