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Convert column classes in data.table
...ng data.table: How do I convert column classes? Here is a simple example: With data.frame I don't have a problem converting it, with data.table I just don't know how:
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Dispelling the UIImage imageNamed: FUD
Edit Feb 2014: Note that this question dates from iOS 2.0! Image requirements and handling have moved on a lot since then. Retina makes images bigger and loading them slightly more complex. With the built in support for iPad and retina images, you should certainly use ImageNamed in your code .
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Find all files with name containing string
...e. I have seen locate and find commands that can find files beginning with something first_word* or ending with something *.jpg .
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CSS background image to fit width, height should auto-scale in proportion
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There is a CSS3 property for this, namely background-size (compatibility check). While one can set length values, it's usually used with the special values contain and cover. In your specific case, you should use cover:
body {
background-image: url(images/background.svg);
backgroun...
href=“tel:” and mobile numbers
If I use tel: I should write the international phone code, like that.
5 Answers
5
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How to cut an entire line in vim and paste it?
... command in vim, but I need something which will delete an entire line and it should allow me to paste the same line somewhere else.
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mysql_fetch_array()/mysql_fetch_assoc()/mysql_fetch_row()/mysql_num_rows etc… expects parameter 1 to
...ir respective query functions/methods. You need to test for that error condition and handle it accordingly.
mysql_* extension:
NOTE The mysql_ functions are deprecated and have been removed in php version 7.
Check $result before passing it to mysql_fetch_array. You'll find that it's false bec...
How to sum up elements of a C++ vector?
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Actually there are quite a few methods.
int sum_of_elems = 0;
C++03
Classic for loop:
for(std::vector<int>::iterator it = vector.begin(); it != vector.end(); ++it)
sum_of_elems += *it;
Using a standard algorithm:
#include &l...
What are the differences between a clustered and a non-clustered index?
...red index
Both types of index will improve performance when select data with fields that use the index but will slow down update and insert operations.
Because of the slower insert and update clustered indexes should be set on a field that is normally incremental ie Id or Timestamp.
SQL Server w...
Warning: mysql_connect(): [2002] No such file or directory (trying to connect via unix:///tmp/mysql.
I'm trying to connect to my MySQL DB with the Terminal on my Apple (With PHP).
17 Answers
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