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Good MapReduce examples [closed]
...erations that you can do in MapReduce is the set of normal SQL operations: SELECT, SELECT WHERE, GROUP BY, ect.
Another good example is matrix multiply, where you pass one row of M and the entire vector x and compute one element of M * x.
...
Explicitly calling return in a function or not
...son for not using explicit return. The following plot is created from data selected this way:
bench_nor2 <- function(x,repeats) { system.time(rep(
# without explicit return
(function(x) vector(length=x,mode="numeric"))(x)
,repeats)) }
bench_ret2 <- function(x,repeats) { system.time(rep(
# wi...
How to define a custom ORDER BY order in mySQL
...in the order you specify.
The second will involve a case somewhere, i.e.
SELECT * FROM table
ORDER BY CASE Language
WHEN 'ENU' THEN 3
WHEN 'JPN' THEN 2
WHEN 'DAN' THEN 1
ELSE 0
END DESC, ID ASC
Performance-wise the ENUM method will return faster results, but be more hassle if you...
Rails: Default sort order for a rails model?
...hen it gets used for actions like where's limiting (filtering) the default selection (a bad idea for a default) rather than just being used for ordering results.
For where selections, just use the regular named scopes. and add that scope on in the query, e.g. Book.all.published where published is a ...
Disable resizing of a Windows Forms form
...
First, select the form.
Then, go to the properties menu.
And change the property "FormBorderStyle" from sizable to Fixed3D or FixedSingle.
share
...
require file as string
...
The selected answer is deprecated and not recommended anymore.
NodeJS documentation suggests other approaches like:
loading modules via some other Node.js program
but it does not expand any more.
You can use a very simple libr...
Removing highcharts.com credits link
... server locally for exporting the charts. When download as png/jpeg/pdf is selected from the top right corner of the chart , the Highcharts demo page is displayed. so how can stop that redirection can please help me
– Edit
Oct 12 '17 at 8:02
...
How do I stop Skype from using HTTP or HTTPS ports 80 and 443? [closed]
...t 80 and port 443, open the Skype window, then click on the Tools menu and select Options. Click on the Advanced tab, and go to the Connection sub-tab. Untick or uncheck the checkbox for Use port 80 and 443 as an alternative for additional incoming connections option. Click on the Save button and th...
How to use a switch case 'or' in PHP
...le switch(), and when I'm working in a C-ish language I really miss having Select Case, which is really a shorthand way of saying "there's a big block of if, else if, else-if... here".
– Stan Rogers
Oct 9 '10 at 7:50
...
DateTime2 vs DateTime in SQL Server
...= '5/5/2010 23:59:59.999'
declare @d3 datetime = '5/5/2010 23:59:59.997'
select @d1 as 'IAmMay6BecauseOfRounding', @d2 'May5', @d3 'StillMay5Because2msEarlier'
Avoiding this implicit rounding is a significant reason to move to DateTime2. Implicit rounding of dates clearly causes confusion:
St...