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Why prefer two's complement over sign-and-magnitude for signed numbers?
...ou that a block of memory is a signed or unsigned integer or a double or a string or something else. The raw data is whatever type you choose to interpret it as.
– Welbog
Jul 2 '15 at 19:23
...
Test if string is a number in Ruby on Rails
...
Create is_number? Method.
Create a helper method:
def is_number? string
true if Float(string) rescue false
end
And then call it like this:
my_string = '12.34'
is_number?( my_string )
# => true
Extend String Class.
If you want to be able to call is_number? directly on the string...
Calculate MD5 checksum for a file
...terested in comparing the hashes.)
If you need to represent the hash as a string, you could convert it to hex using BitConverter:
static string CalculateMD5(string filename)
{
using (var md5 = MD5.Create())
{
using (var stream = File.OpenRead(filename))
{
var ha...
WAMP 403 Forbidden message on Windows 7
... I couldnt format my address line in that last comment so there's an extra "'" in it just ignore that sorry if it confuses anyone.
– Jeremy
May 1 '12 at 19:57
...
Show MySQL host via SQL Command
...ink you try to get the remote host of the conneting user...
You can get a String like 'myuser@localhost' from the command:
SELECT USER()
You can split this result on the '@' sign, to get the parts:
-- delivers the "remote_host" e.g. "localhost"
SELECT SUBSTRING_INDEX(USER(), '@', -1)
-- deli...
Java executors: how to be notified, without blocking, when a task completes?
...blic class GetTaskNotificationWithoutBlocking {
public static void main(String... argv) throws Exception {
ExampleService svc = new ExampleService();
GetTaskNotificationWithoutBlocking listener = new GetTaskNotificationWithoutBlocking();
CompletableFuture<String> f = Completable...
How do I do a case-insensitive string comparison?
How can I do case insensitive string comparison in Python?
9 Answers
9
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How to get the first five character of a String
I have read this question to get first char of the string. Is there a way to get the first n number of characters from a string in C#?
...
How to get the primary IP address of the local machine on Linux and OS X? [closed]
...oking for a command line solution that would return me the primary (first) IP address of the localhost, other than 127.0.0.1
...
Select rows which are not present in other table
...ll of them standard SQL.
NOT EXISTS
Often fastest in Postgres.
SELECT ip
FROM login_log l
WHERE NOT EXISTS (
SELECT -- SELECT list mostly irrelevant; can just be empty in Postgres
FROM ip_location
WHERE ip = l.ip
);
Also consider:
What is easier to read in EXISTS subque...