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How to append rows to an R data frame
...tion specific to my problem, which involves appending rows to an R data frame.
7 Answers
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Undefined, unspecified and implementation-defined behavior
...undefined behavior in C and C++? What about unspecified behavior and implementation-defined behavior? What is the difference between them?
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Why switch is faster than if
Lots of Java books describe the switch statement as being faster than the if else statement. But I did not find out anywhere why switch is faster than if .
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Pointer expressions: *ptr++, *++ptr and ++*ptr
Recently I have come across this problem which I am unable to understand by myself.
10 Answers
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How to use Regular Expressions (Regex) in Microsoft Excel both in-cell and loops
...icrosoft Visual Basic for Applications" window select "Tools" from the top menu.
Select "References"
Check the box next to "Microsoft VBScript Regular Expressions 5.5" to include in your workbook.
Click "OK"
Step 2: Define your pattern
Basic definitions:
- Range.
E.g. a-z matches an lower c...
What are the main performance differences between varchar and nvarchar SQL Server data types?
... it is far harder to go back and add support for multilingual text/messages, time zones, units of measure and currency, so everyone MUST always code these in their application from day one, ALWAYS (even if it is only on your home page web app)!
– KM.
Ju...
How to trace the path in a Breadth-First Search?
...n.wikipedia.org/wiki/Breadth-first_search first.
Below is a quick implementation, in which I used a list of list to represent the queue of paths.
# graph is in adjacent list representation
graph = {
'1': ['2', '3', '4'],
'2': ['5', '6'],
'5': ['9', '10'],
'4': ['...
In git how is fetch different than pull and how is merge different than rebase?
...just cant understand this. I been reading a lot on the web and books and something is just not staying in my head. Can someone please give me the dummy version of the following:
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Which is faster: Stack allocation or Heap allocation
This question may sound fairly elementary, but this is a debate I had with another developer I work with.
23 Answers
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Good or bad practice? Initializing objects in getter
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What you have here is a - naive - implementation of "lazy initialization".
Short answer:
Using lazy initialization unconditionally is not a good idea. It has its places but one has to take into consideration the impacts this solution has.
Background and explana...