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How does delete[] “know” the size of the operand array?
... but to get the size myself in that same function I have to pass around an extra parameter. Does that make any sense?
– Mark Ruzon
Jun 11 '09 at 0:16
28
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Show percent % instead of counts in charts of categorical variables
... shows what additional columns are added to the data frame by ggplot2. All extra columns are of the form ..variable...
– Ramnath
May 17 '14 at 13:42
1
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Oracle Differences between NVL and Coalesce
...om dual; would work as NVL will do an implicit conversion of numeric 10 to string.
select coalesce('abc',10) from dual; will fail with Error - inconsistent datatypes: expected CHAR got NUMBER
Example for UNION use-case
SELECT COALESCE(a, sysdate)
from (select null as a from dual
union
...
Understanding exactly when a data.table is a reference to (vs a copy of) another data.table
... <- DT[,new:=1L]
because the RHS already changed DT by reference. The extra DT <- is to misunderstand what := does. You can write it there, but it's superfluous.
DT is changed by reference, by :=, EVEN WITHIN FUNCTIONS :
f <- function(X){
X[,new2:=2L]
return("something else")
}...
How can I initialize base class member variables in derived class constructor?
...ase from Member idiom. It's not a code free solution, you'd have to add an extra layer of inheritance, but it gets the job done. To avoid boilerplate code you could use boost's implementation
share
|
...
MySQL string replace
...w');
-> 'WwWwWw.mysql.com'
http://dev.mysql.com/doc/refman/5.0/en/string-functions.html#function_replace
Note that it's easier if you make that an alias when using SELECT
SELECT REPLACE(string_column, 'search', 'replace') as url....
...
Custom fonts and XML layouts (Android)
...ew;
public class TextViewPlus extends TextView {
private static final String TAG = "TextView";
public TextViewPlus(Context context) {
super(context);
}
public TextViewPlus(Context context, AttributeSet attrs) {
super(context, attrs);
setCustomFont(context, ...
jquery IDs with spaces
...
Then up to 4 backslashes if the JavaScript is itself a string constant in some other language.
– Brilliand
Feb 5 '14 at 17:29
2
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Check if an element is present in an array [duplicate]
...
!==-1 [extra chars]
– Francisc
Aug 7 '13 at 12:22
3
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How to create id with AUTO_INCREMENT on Oracle?
...g. 1,2,3,....
GUID. globally univeral identifier, as a RAW datatype.
GUID (string). Same as above, but as a string which might be easier to handle in some languages.
x is the identity column. Substitute FOO with your table name in each of the examples.
-- numerical identity, e.g. 1,2,3...
creat...