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Function to return only alpha-numeric characters from string?
...restricted to just A-Z.
Try this to remove everything except a-z, A-Z and 0-9:
$result = preg_replace("/[^a-zA-Z0-9]+/", "", $s);
If your definition of alphanumeric includes letters in foreign languages and obsolete scripts then you will need to use the Unicode character classes.
Try this to le...
Google Map API v3 — set bounds and center
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answered Feb 5 '10 at 7:14
spencercoolyspencercooly
5,79822 gold badges2020 silver badges1515 bronze badges
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Concept behind these four lines of tricky C code
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The number 7709179928849219.0 has the following binary representation as a 64-bit double:
01000011 00111011 01100011 01110101 01010011 00101011 00101011 01000011
+^^^^^^^ ^^^^---- -------- -------- -------- -------- -------- --------
+...
How do you know when to use fold-left and when to use fold-right?
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105
You can transfer a fold into an infix operator notation (writing in between):
This example fol...
How do I add a Maven dependency in Eclipse?
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205
On the top menu bar, open Window -> Show View -> Other
In the Show View window, open Mav...
Trying to understand CMTime and CMTimeMake
1) CMTimeMake(1,10) means duration of 1 second and timescale of 10, or 10 frames per second. This means 1s duration of video with 10 frames?
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How to get last items of a list in Python?
...the python CLI interpreter:
>>> a = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]
>>> a
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]
>>> a[-9:]
[4, 5, 6, 7, 8, 9, 10, 11, 12]
the important line is a[-9:]
s...
Why is transposing a matrix of 512x512 much slower than transposing a matrix of 513x513?
...t has 4 lines, each holding 64 bytes. We first attempt to read the address 0x2710, which goes in set 28. And then we also attempt to read addresses 0x2F00, 0x3700, 0x3F00 and 0x4700. All of these belong to the same set. Before reading 0x4700, all lines in the set would have been occupied. Reading th...
Why does ~True result in -2?
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240
int(True) is 1.
1 is:
00000001
and ~1 is:
11111110
Which is -2 in Two's complement1
1 Fl...
How to read and write excel file
...SSFWorkbook wb = new HSSFWorkbook(fs);
HSSFSheet sheet = wb.getSheetAt(0);
HSSFRow row;
HSSFCell cell;
int rows; // No of rows
rows = sheet.getPhysicalNumberOfRows();
int cols = 0; // No of columns
int tmp = 0;
// This trick ensures that we get the data properly ev...