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Meaning of $? (dollar question mark) in shell scripts
...ure.
Hence when scripting; I tend to use the following syntax
if [ $? -eq 0 ]; then
# do something
else
# do something else
fi
The comparison is to be done on equals to 0 or not equals 0.
** Update Based on the comment: Ideally, you should not use the above code block for comparison, refer t...
Postgresql: password authentication failed for user “postgres”
I have installed PostgreSQL 8.4, Postgres client and Pgadmin 3. Authentication failed for user "postgres" for both console client and Pgadmin. I have typed user as "postgres" and password "postgres", because it worked before. But now authentication is failed. I did it before a couple of times withou...
Django Admin - change header 'Django administration' text
...this in url.py admin.site.site_header = 'My Administration' admin.site.index_title = ('My Admin') admin.site.site_title = ('My Admin page')
– Ashish Gupta
Jul 8 '17 at 16:51
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HTML5 record audio to file
...cording demo available at: http://webaudiodemos.appspot.com/AudioRecorder/index.html
It allows you to record audio in the browser, then gives you the option to export and download what you've recorded.
You can view the source of that page to find links to the javascript, but to summarize, there's...
Convert tabs to spaces in Notepad++
...
The best answer for the question (perhaps not as the author intended it) is the tabs to spaces plugin offered below. The question asks for all tabs to spaces, while this answer only converts leading spaces. If, for example, you need to convert tab...
Replace multiple characters in a C# string
..., this reads:
"Search for ; or , or \t or \r or (space) or exactly two sequential \n and replace it with \n"
In C#, you could do the following: (after importing System.Text.RegularExpressions)
Regex pattern = new Regex("[;,\t\r ]|[\n]{2}");
pattern.Replace(myString, "\n");
...
Is there a float input type in HTML5?
...0 (1 min, 10 sec)<br />
</form>
As usual, I'll add a quick note: remember that client-side validation is just a convenience to the user. You must also validate on the server-side!
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Are JavaScript strings immutable? Do I need a “string builder” in JavaScript?
...e it slower...
function StringBuilder() {
this._array = [];
this._index = 0;
}
StringBuilder.prototype.append = function (str) {
this._array[this._index] = str;
this._index++;
}
StringBuilder.prototype.toString = function () {
return this._array.join('');
}
Here are performa...
SQLiteDatabase.query method
I am using the query method of SQLiteDatabase. How do I use the query method?
5 Answers
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Speed up the loop operation in R
...
Biggest problem and root of ineffectiveness is indexing data.frame, I mean all this lines where you use temp[,].
Try to avoid this as much as possible. I took your function, change indexing and here version_A
dayloop2_A <- function(temp){
res <- numeric(nrow(te...