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How to get pixel data from a UIImage (Cocoa Touch) or CGImage (Core Graphics)?
... CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
unsigned char *rawData = (unsigned char*) calloc(height * width * 4, sizeof(unsigned char));
NSUInteger bytesPerPixel = 4;
NSUInteger bytesPerRow = bytesPerPixel * width;
NSUInteger bitsPerComponent = 8;
CGContextRef c...
How to read data when some numbers contain commas as thousand separator?
...thod using the setAs function like so:
setClass("num.with.commas")
setAs("character", "num.with.commas",
function(from) as.numeric(gsub(",", "", from) ) )
Then run read.csv like:
DF <- read.csv('your.file.here',
colClasses=c('num.with.commas','factor','character','numeric','num.w...
Replace all non-alphanumeric characters in a string
I have a string with which i want to replace any character that isn't a standard character or number such as (a-z or 0-9) with an asterisk. For example, "h^&ell`.,|o w]{+orld" is replaced with "h*ell*o*w*orld". Note that multiple characters such as "^&" get replaced with one asterisk. How would I go...
How to atomically delete keys matching a pattern using Redis
...helped me out. Another variant if your redis keys contain quotes or other characters that mess up xargs: redis-cli KEYS "prefix:*" | xargs --delim='\n' redis-cli DEL
– overthink
Sep 16 '11 at 13:31
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Difference between Ctrl+Shift+F and Ctrl+I in Eclipse
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Ctrl+Shift+F formats the selected line(s) or the whole source code if you haven't selected any line(s) as per the formatter specified in your Eclipse, while Ctrl+I gives proper indent to the selected line(s) or the current line if you haven't selecte...
How to select multiple files with ?
How to select multiple files with <input type="file"> ?
9 Answers
9
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[since C++11] std::array的使用 - C/C++ - 清泛网 - 专注C/C++及内核技术
...-------------------
RUN_GTEST(ArrayTest, CStyleArray, @);
// use array<char> as a fix sized c-string.
array<char, 100> str = {0}; // all elements initialized with 0.
char *p = str.data();
strcpy(p, "hello world");
printf("%s\n", p); // hello world
END_TEST;
上...
Checking if a string array contains a value, and if so, getting its position
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How do I check individual values? When I tried checking a char array for a char, I got a message that char can't be converted to System.Predicate<char>
– Aaron Franke
May 27 at 15:09
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How to add column if not exists on PostgreSQL?
...s, _col text, _type regtype)
RETURNS bool AS
$func$
BEGIN
IF EXISTS (SELECT 1 FROM pg_attribute
WHERE attrelid = _tbl
AND attname = _col
AND NOT attisdropped) THEN
RETURN FALSE;
ELSE
EXECUTE format('ALTER TABLE %s ADD COLUMN %I %s...
SQL Server Installation - What is the Installation Media Folder?
... Server 2019 Developer version. Was lost with dialog prompted from step 3 "Select installation media". This Andy Leonard blog helped me: 1. Downloaded installation package from SQL Server downloads. 2. Launch downloaded wizard > Select installation type > Download media 3. Right-click on the d...