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Programmatically creating Markdown tables in R with KnitR
...:) Please note that you might also use the generic S3 method to save a few chars to type, like: pander(head(iris)[, 1:3])
– daroczig
Mar 19 '13 at 9:23
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What is uint_fast32_t and why should it be used instead of the regular int and uint32_t?
...ven addressable. In such a case working on them requires additional ops to extract the 32-bits from, say, 64-bit aligned units. See also the linked question. C++ standard is written so that it could work on a machine that has 37-bit words... so no 32-bit type there at all.
– Ya...
When should I use Lazy?
...erties for Name, PhoneNumber, and Orders. Name and PhoneNumber are regular strings but Orders is a navigation property that returns a list of every order the customer ever made.
You often might want to go through all your customer's and get their name and phone number to call them. This is a very q...
Simple way to transpose columns and rows in SQL?
...ate the list of items to UNPIVOT and PIVOT. This is then added to a query string to be executed. The plus of the dynamic version is if you have a changing list of colors and/or names this will generate the list at run-time.
All three queries will produce the same result:
| NAME | RED | GREEN | BL...
Fetch the row which has the Max value for a column
...Y User)
EDIT: Just tried it for real:
SQL> create table MyTable (usr char(1), dt date);
SQL> insert into mytable values ('A','01-JAN-2009');
SQL> insert into mytable values ('B','01-JAN-2009');
SQL> insert into mytable values ('A', '31-DEC-2008');
SQL> insert into mytable values ('...
Is SHA-1 secure for password storage?
... that cost N once and can thereafter attack many passwords with very small extra cost per password.
If the pre-computed table is a rainbow table, then N can be somewhat bigger, because storage cost is reduced. The bottleneck on N becomes the CPU power that the attacker can muster, not the size of hi...
Are Java static calls more or less expensive than non-static calls?
...java.io.*;
class StaticVsInstanceBenchmark
{
public static void main( String[] args ) throws Exception
{
StaticVsInstanceBenchmark program = new StaticVsInstanceBenchmark();
program.run();
}
static final int DURATION = 1000;
public void run() throws Exception
...
Rails respond_with: how does it work?
...tion => posts_path)
# Note that if you want to pass a URL with a query string
# then the location option would be needed.
# /users?scope=active
respond_with(@user, :location => users_path(:scope => 'active'))
As an alternative, the responders gem not only provides some modules for over...
When exactly are onSaveInstanceState() and onRestoreInstanceState() called?
...
String activityState;
@Override
public void onCreate(Bundle savedInstanceState) {
// call the super class onCreate to complete the creation of activity like
// the view hierarchy
super.onCreate(savedInstanceState);
// rec...
How to slice an array in Bash
... defaults to
zero, an omitted second index defaults to the size of the string being
sliced.
>>> local a=(0 1 2 3 4 5)
>>> # from the beginning to position 2 (excluded)
>>> echo $(array.slice 0:2 "${a[@]}")
>>> echo $(array.slice :2 "${a[@]}...