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[ :Unexpected operator in shell programming [duplicate]
...on which name you use. You can have the script run with bash automatically by changing the first line to #!/bin/bash and making the file executable, and just running ./choose.sh.
– Tyler McHenry
Aug 5 '10 at 1:17
...
Can every recursion be converted into iteration?
...roves it if memory serves. In lay terms, it states that what is computable by recursive functions is computable by an iterative model (such as the Turing machine) and vice versa. The thesis does not tell you precisely how to do the conversion, but it does say that it's definitely possible.
In many ...
How to include “zero” / “0” results in COUNT aggregate?
...
LEFT JOIN appointment ON person.person_id = appointment.person_id
GROUP BY person.person_id;
The reason why this is working, is that the outer (left) join will return NULL for those persons that do not have an appointment. The aggregate function count() will not count NULL values and thus you'l...
In what cases could `git pull` be harmful?
...
Summary
By default, git pull creates merge commits which add noise and complexity to the code history. In addition, pull makes it easy to not think about how your changes might be affected by incoming changes.
The git pull command ...
When should we use mutex and when should we use semaphore
...a mutex when you (thread) want to execute code that should not be executed by any other thread at the same time. Mutex 'down' happens in one thread and mutex 'up' must happen in the same thread later on.
e.g.: If you are deleting a node from a global linked list, you do not want another thread to mu...
Accessing dict_keys element by index in Python3
I'm trying to access a dict_key's element by its index:
6 Answers
6
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How to submit a form with JavaScript by clicking a link?
...id">submit</button>
</form>
var form = document.getElementById("form-id");
document.getElementById("your-id").addEventListener("click", function () {
form.submit();
});
Enclose the latter JavaScript code by an DOMContentLoaded event (choose only load for backward compatiblity) ...
Select multiple columns in data.table by their numeric indices
...ta.table)
dt <- data.table(a = 1, b = 2, c = 3)
# select single column by index
dt[, 2]
# b
# 1: 2
# select multiple columns by index
dt[, 2:3]
# b c
# 1: 2 3
# select single column by name
dt[, "a"]
# a
# 1: 1
# select multiple columns by name
dt[, c("a", "b")]
# a b
# 1: 1 2
...
How to show disable HTML select option in by default?
... You don't need to put the true or disabled values. you can get by doing <option selected disabled>Choose Tagging</option>
– Sam Eaton
Feb 17 '16 at 3:37
19
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Turning off “created by” stamp when generating files in IntelliJ
... Code Templates area of the settings dialog. In Idea 15+ you can get there by typing ctrl+shift+A on windows or cmd+shift+A on osx and then typing Include Templates in the popup action search dialog. There should be a tab called Includes on which you will find the Java and ActionScript file types, a...