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How to append contents of multiple files into one file
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@radical7 Thanks. Actually, my files are like foo_1, foo_2, foo_3. I tried to modify your code as - cat "$filename_"{1,2,3}".txt" , but it did not work.
– Steam
Aug 2 '13 at 0:09
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Is arr.__len__() the preferred way to get the length of an array in Python?
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my_list = [1,2,3,4,5]
len(my_list)
# 5
The same works for tuples:
my_tuple = (1,2,3,4,5)
len(my_tuple)
# 5
And strings, which are really just arrays of characters:
my_string = 'hello world'
len(my_string)
# 11
It was in...
How to tell if a tag failed to load
... };
var fail = function () {
if (!scriptTag.__es) {
scriptTag.__es = true;
scriptTag.id = 'failed';
args.failure(scriptTag);
}
};
scriptTag.onload = function () {
...
SQL Add foreign key to existing column
...rst and then re-run the statement.
ALTER TABLE Employees
ADD CONSTRAINT FK_ActiveDirectories_UserID FOREIGN KEY (UserID)
REFERENCES ActiveDirectories(id);
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Regex to Match Symbols: !$%^&*()_+|~-=`{}[]:";'?,./
...l character in character classes, so it needs to be first:
/[-!$%^&*()_+|~=`{}\[\]:";'<>?,.\/]/
You also need to escape the other regular expression metacharacters.
Edit:
The hyphen is special because it can be used to represent a range of characters. This same character class can be ...
Finding the index of an item in a list
...atch, you can give index a hint. For instance, in this snippet, l.index(999_999, 999_990, 1_000_000) is roughly five orders of magnitude faster than straight l.index(999_999), because the former only has to search 10 entries, while the latter searches a million:
>>> import timeit
>>&g...
How can I uninstall an application using PowerShell?
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$app = Get-WmiObject -Class Win32_Product | Where-Object {
$_.Name -match "Software Name"
}
$app.Uninstall()
Edit: Rob found another way to do it with the Filter parameter:
$app = Get-WmiObject -Class Win32_Product `
-Filter "N...
Create singleton using GCD's dispatch_once in Objective-C
...er here: instancetype
+ (instancetype)sharedInstance
{
static dispatch_once_t once;
static id sharedInstance;
dispatch_once(&once, ^
{
sharedInstance = [self new];
});
return sharedInstance;
}
+ (Class*)sharedInstance
{
static dispatch_once_t once;
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How to get the error message from the error code returned by GetLastError()?
...rror message has been recorded
LPSTR messageBuffer = nullptr;
size_t size = FormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
NULL, errorMessageID, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), (LPSTR)&a...
How do you round a floating point number in Perl?
...foreach my $i ( 0.5, 1.5, 2.5, 3.5 ) {
printf "$i -> %.0f\n", $i;
}
__END__
0.5 -> 0
1.5 -> 2
2.5 -> 2
3.5 -> 4
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