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How to use clock() in C++
How do I call clock() in C++ ?
7 Answers
7
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How do I write the 'cd' command in a makefile?
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It is actually executing the command, changing the directory to some_directory, however, this is performed in a sub-process shell, and affects neither make nor the shell you're working from.
If you're looking to perform more tasks wit...
How do I get the base URL with PHP?
... XAMPP on Windows Vista. In my development, I have http://127.0.0.1/test_website/ .
22 Answers
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How can you profile a Python script?
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Python includes a profiler called cProfile. It not only gives the total running time, but also times each function separately, and tells you how many times each function was called, making it easy to determine where you should make optimizations.
You c...
How is the undo tree used in Vim?
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See also :h undo-redo, which lists all the commands and their usage.
There are two ways to traverse the undo tree. One is to go "back in time". g+ and g- will traverse all of the nodes in the tree in chronological or reverse-chronological order (which can...
When saving, how can you check if a field has changed?
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Essentially, 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.CharF...
Adding :default => true to boolean in existing Rails column
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change_column is a method of ActiveRecord::Migration, so you can't call it like that in the console.
If you want to add a default value for this column, create a new migration:
rails g migration add_default_value_to_show_attribute
Then in the migration created:
# That's the more generic way t...
Longest line in a file
...ing for a simple way to find the length of the longest line in a file. Ideally, it would be a simple bash shell command instead of a script.
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snprintf and Visual Studio 2010
... the expected behavior for snprintf:
int snprintf( char* buffer, std::size_t buf_size, const char* format, ... );
Writes at most buf_size - 1 characters to a buffer. The resulting
character string will be terminated with a null character, unless
buf_size is zero. If buf_size is zero, nothi...
What does character set and collation mean exactly?
...a symbol, the number 0 is the
encoding for 'A', and the combination
of all four letters and their
encodings is a character set.
Now, suppose that we want to compare
two string values, 'A' and 'B'. The
simplest way to do this is to look at
the encodings: 0 for 'A' and 1 for
'B'. Be...