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In STL maps, is it better to use map::insert than []?
...<std::endl;
}
};
int Sample::_noOfObjects = 0;
int main(int argc, char* argv[])
{
Sample sample;
std::map<int,Sample> map;
map.insert( std::make_pair<int,Sample>( 1, sample) );
//map[1] = sample;
return 0;
}
...
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 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...
Retrieve specific commit from a remote Git repository
...ubmodule pointer).
Only objects reachable from the branch tips, i.e. the union of advertised branches and branches hidden by transfer.hideRefs, will be processed.
Note that there is an associated cost of having to walk back the history to check the reachability.
This feature can be used whe...
Select unique or distinct values from a list in UNIX shell script
I have a ksh script that returns a long list of values, newline separated, and I want to see only the unique/distinct values. It is possible to do this?
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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...
Selecting a row of pandas series/dataframe by integer index
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The primary purpose of the DataFrame indexing operator, [] is to select columns.
When the indexing operator is passed a string or integer, it attempts to find a column with that particular name and return it as a Series.
So, in the question above: df[2] searches for a column name matchin...
In MySQL, how to copy the content of one table to another table within the same database?
...
INSERT INTO TARGET_TABLE SELECT * FROM SOURCE_TABLE;
EDIT: or if the tables have different structures you can also:
INSERT INTO TARGET_TABLE (`col1`,`col2`) SELECT `col1`,`col2` FROM SOURCE_TABLE;
EDIT: to constrain this..
INSERT INTO TARGET_TAB...
Android Gallery on Android 4.4 (KitKat) returns different URI for Intent.ACTION_GET_CONTENT
...tyForResult(Intent.createChooser(intent, getResources().getString(R.string.select_picture)),GALLERY_INTENT_CALLED);
} else {
Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT);
intent.addCategory(Intent.CATEGORY_OPENABLE);
intent.setType("image/jpeg");
startActivityForResult(int...
List of tables, db schema, dump etc using the Python sqlite3 API
....tab
job snmptarget t1 t2 t3
sqlite> select name from sqlite_master where type = 'table';
job
t1
t2
snmptarget
t3
sqlite> .schema job
CREATE TABLE job (
id INTEGER PRIMARY KEY,
data VARCHAR
);
sqlite> select sql from sqlite_master where type = 'ta...