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Does Java casting introduce overhead? Why?
... nice and fast :) For interfaces I would assume no worse than a small hashtable or btree ?
– peterk
Jan 12 '12 at 19:34
...
How to read a .xlsx file using the pandas Library in iPython?
... file using the Pandas Library of python and port the data to a postgreSQL table.
6 Answers
...
What does “S3 methods” mean in R?
...
method calls look like canvas$drawRect("blue"). RC objects are also
mutable: they don’t use R’s usual copy-on-modify semantics, but are
modified in place. This makes them harder to reason about, but allows
them to solve problems that are difficult to solve with S3 or S4.
There...
Valid values for android:fontFamily and what they map to?
...erif"
android:textStyle="bold" />
to the desired values from this table:
Font | android:fontFamily | android:textStyle
-------------------------|-----------------------------|-------------------
Roboto Thin | sans-serif-thin |
Roboto Li...
SPAN vs DIV (inline-block)
...strong and em, can only contain other phrasing elements: you can’t put a table inside a cite for instance. Most flow content such as div and li can contain all types of flow content (as well as phrasing content), but there are a few exceptions: p, pre, and th are examples of non-phrasing flow cont...
How to avoid isset() and empty()
...hat may or may not be set by a controller, you'll just have to check:
<table>
<?php if (!empty($foo) && is_array($foo)) : ?>
<?php foreach ($foo as $bar) : ?>
<tr>...</tr>
<?php endforeach; ?>
<?php else : ?>
...
Explain the use of a bit vector for determining if all characters are unique
...of both operands to left and right of it.
So what we have here is a hash table which is being stored in a 32 bit binary number every time the checker gets or'd ( checker |= (1 << val)) with the designated binary value of a letter its corresponding bit it is being set to true.
The character's...
What's with 181783497276652981 and 8682522807148012 in Random (Java 7)?
...o Java?
Yes, seems to be a typo.
Does 181783497276652981 have an acceptable merit?
This could be determined using the evaluation algorithm presented in the paper. But the merit of the "original" number is probably higher.
And why was 8682522807148012 chosen?
Seems to be random. It could ...
What is the claims in ASP .NET Identity
...nformation, when data
addes to AspNetUserClaims and what situations this table using for?
When you are in a situation where a Role-Based Security is not used, and you chose to use Claim-Based
Security, you would need to utilize AspNetUserClaims table.
For how to use Claims in ASP.NET Identity, s...
How do I obtain a Query Execution Plan in SQL Server?
...mat.
Notes:
Because there are so many factors involved (ranging from the table and index schema down to the data stored and the table statistics) you should always try to obtain an execution plan from the database you are interested in (normally the one that is experiencing a performance problem)....