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Factors in R: more than an annoyance?
...y they are useful because model fitting packages like lme4 use factors and ordered factors to differentially fit models and determine the type of contrasts to use. And graphing packages also use them to group by. ggplot and most model fitting functions coerce character vectors to factors, so the res...
Accessing a Dictionary.Keys Key through a numeric index
...t = mydict.Keys.ElementAt(mydict.Count -1);
You should not depend on the order of keys in a Dictionary. If you need ordering, you should use an OrderedDictionary, as suggested in this answer. The other answers on this page are interesting as well.
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Group by month and year in MySQL
...aryDateTime) DESC
Should use DESC for both YEAR and Month to get correct order.
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How to order results with findBy() in Doctrine
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The second parameter of findBy is for ORDER.
$ens = $em->getRepository('AcmeBinBundle:Marks')
->findBy(
array('type'=> 'C12'),
array('id' => 'ASC')
);
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How to delete duplicate rows in SQL Server?
...4], [col5], [col6], [col7],
RN = ROW_NUMBER()OVER(PARTITION BY col1 ORDER BY col1)
FROM dbo.Table1
)
DELETE FROM CTE WHERE RN > 1
DEMO (result is different; I assume that it's due to a typo on your part)
COL1 COL2 COL3 COL4 COL5 COL6 COL7
john 1 1 1...
IPN vs PDT in Paypal
...etc, and thus you really should implement it.
PayPal's PDT system sends order confirmations to merchant sites that use PayPal Payments Standard and lets them authenticate this information. Such sites can then display this data locally in an "order confirmation" page.
When to Use PDT?
IPN provid...
Laravel 4: how to “order by” using Eloquent ORM [duplicate]
Simple question - how do I order by 'id' descending in Laravel 4.
3 Answers
3
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Comparing strings by their alphabetical order
I want to compare the two above string by their alphabetic order (which in this case "Project" then "Sunject" as "P" comes before "S").
Does anyone know how to do that in Java?
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Sort a list from another list IDs
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docs = docs.OrderBy(d => docsIds.IndexOf(d.Id)).ToList();
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Get records with max value for each group of grouped SQL results
...uper-simple way to do this in mysql:
select *
from (select * from mytable order by `Group`, age desc, Person) x
group by `Group`
This works because in mysql you're allowed to not aggregate non-group-by columns, in which case mysql just returns the first row. The solution is to first order the data...