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Difference between volatile and synchronized in Java
...ariables cannot be reordered with each other. The difference is that it is now no longer so easy to reorder normal field accesses around them. Writing to a volatile field has the same memory effect as a monitor release, and reading from a volatile field has the same memory effect as a monitor acquir...
Check if a temporary table exists and delete if it exists before creating a temporary table
...olumn later, it will give an error saying "invalid column". Please let me know what I am doing wrong.
15 Answers
...
How do I profile memory usage in Python?
...ozen importlib._bootstrap>"),
tracemalloc.Filter(False, "<unknown>"),
))
top_stats = snapshot.statistics(key_type)
print("Top %s lines" % limit)
for index, stat in enumerate(top_stats[:limit], 1):
frame = stat.traceback[0]
# replace "/path/to/module/...
Uploading images using Node.js, Express, and Mongoose
...rd it referred that way and I'm going to go ahead and say that these guys know best developer.mozilla.org/en-US/docs/JavaScript/Guide/… so I guess we are both wrong ;)
– srquinn
Apr 19 '13 at 0:17
...
module.exports vs exports in Node.js
... want to export a constructor function then there is something you should know about using module.exports or exports;(Remember again that module.exports will be returned when you require something, not export).
module.exports = function Something() {
console.log('bla bla');
}
Now typeof retur...
How can I resize an image dynamically with CSS as the browser width/height changes?
...its should make your life way easier, given we have the image of a cat:
Now we want this cat inside our code, while respecting aspect ratios:
img {
width: 100%;
height: auto;
}
<img src="https://www.petmd.com/sites/default/files/petmd-cat-happy-10.jpg" alt="cat">
So far ...
Random color generator
...
@Mohsen, FYI every now and then your code produces invalid 5 digit number
– rochal
Nov 5 '11 at 18:05
6
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Conversion from Long to Double in Java
...
I did. Parsing a string to do this (now edited out of the answer) will degrade performance by many orders of magnitude. Boxing is less expensive but still worth avoiding, especially in cases like this (using new) where it can't be elided away.
...
Is < faster than
...- B < 0
A = B --> A - B = 0
A > B --> A - B > 0
Now, when A < B the subtraction has to borrow a high-bit for the subtraction to be correct, just like you carry and borrow when adding and subtracting by hand. This "borrowed" bit was usually referred to as the carry bit a...
if A vs if A is not None:
...
@cedbeu, Seems to depend on the value of A. I tested now python -m timeit -s"a=0" "if a: pass" "else: pass" is faster than python -m timeit -s"a=0" "if a is None: pass" "else: pass" but python -m timeit -s"a=1" "if a: pass" "else: pass" is slower. Might be platform dependant, s...