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How do I print debug messages in the Google Chrome JavaScript Console?
...Oct 20 '08 at 10:20
Sergey IlinskySergey Ilinsky
29.1k99 gold badges4848 silver badges5555 bronze badges
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Create numpy matrix filled with NaNs
...alternatives a[:] = numpy.nan here and a.fill(numpy.nan) as posted by Blaenk:
$ python -mtimeit "import numpy as np; a = np.empty((100,100));" "a.fill(np.nan)"
10000 loops, best of 3: 54.3 usec per loop
$ python -mtimeit "import numpy as np; a = np.empty((100,100));" "a[:] = np.nan"
10000 loops, b...
Get size of folder or file
...s no built-in way to get the size of a folder, you are going to have to walk the directory tree recursively (using the listFiles() method of a file object that represents a directory) and accumulate the directory size for yourself:
public static long folderSize(File directory) {
long length = 0...
When saving, how can you check if a field has changed?
...ally, you want to override the __init__ method of models.Model so that you keep a copy of the original value. This makes it so that you don't have to do another DB lookup (which is always a good thing).
class Person(models.Model):
name = models.CharField()
__original_name = None
def ...
How to format numbers? [duplicate]
...ng() was limited when I first wrote this answer, but the current status looks good.
var n = 100000;
var value = n.toLocaleString(
undefined, // leave undefined to use the browser's locale,
// or use a string like 'en-US' to override it.
{ minimumFractionDigits: 2 }
);
console.lo...
std::vector performance regression when enabling C++11
... with those options you write in your post.
However, if I also enable link time optimization (I also pass the -flto flag to gcc 4.7.2), the results are identical:
(I am compiling your original code, with container.push_back(Item());)
$ g++ -std=c++11 -O3 -flto regr.cpp && perf stat -r 10...
What does the question mark operator mean in Ruby?
What is the purpose of the question mark operator in Ruby?
9 Answers
9
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Delete directories recursively in Java
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You should check out Apache's commons-io. It has a FileUtils class that will do what you want.
FileUtils.deleteDirectory(new File("directory"));
share
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Display number with leading zeros
...ython 2 (and Python 3) you can do:
print "%02d" % (1,)
Basically % is like printf or sprintf (see docs).
For Python 3.+, the same behavior can also be achieved with format:
print("{:02d}".format(1))
For Python 3.6+ the same behavior can be achieved with f-strings:
print(f"{1:02d}")
...
Regex: matching up to the first occurrence of a character
I am looking for a pattern that matches everything until the first occurrence of a specific character, say a ";" - a semicolon .
...