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Reshaping data.frame from wide to long format
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reshape() takes a while to get used to, just as melt/cast. Here is a solution with reshape, assuming your data frame is called d:
reshape(d,
direction = "long",
varying = list(names(d)[3:7]),
v.names = "Value",
idvar = c("Code", "Country"),
...
How to print a date in a regular format?
...isplay them, just use str(). In Python, the good practice is to explicitly cast everything. So just when it's time to print, get a string representation of your date using str(date).
One last thing. When you tried to print the dates, you printed mylist. If you want to print a date, you must print th...
Fastest way to determine if an integer is between two integers (inclusive) with known sets of values
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int inBetween2{ 0 };
for (int i = 1; i < MaxNum; ++i)
{
if (static_cast<unsigned>(num - randVec[i - 1]) <= (randVec[i] - randVec[i - 1]))
++inBetween2;
}
Pay attention that randVec is a sorted vector. For any size of MaxNum the first method beats the second one on my machi...
Fastest way to convert Image to Byte array
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Unable to cast object of type 'System.Byte[]' to type 'System.Drawing.Image'.
– user123
Jun 18 '14 at 12:26
ad...
What does the explicit keyword mean?
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A a4 = A("Venditti");
A* p = new A(1);
A a5 = (A)1;
A a6 = static_cast<A>(1);
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Method has the same erasure as another method in type
... type Set. Generics don't exist in byte code, they're syntactic sugar for casting and provide compile-time type safety.
– Andrzej Doyle
Jan 4 '10 at 13:40
add a comment
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How to convert comma-delimited string to list in Python?
...the case of integers that are included at the string, if you want to avoid casting them to int individually you can do:
mList = [int(e) if e.isdigit() else e for e in mStr.split(',')]
It is called list comprehension, and it is based on set builder notation.
ex:
>>> mStr = "1,A,B,3,4"
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How to handle button clicks using the XML onClick within Fragments
...ckable someFragment;
//...onCreate, etc. instantiating your fragments casting to your interface.
public void myClickMethod(View v) {
someFragment.myClickMethod(v);
}
Fragment:
public class SomeFragment implements XmlClickable {
//...onCreateView, etc.
@Override
public void myClickMet...
How to parameterize @Scheduled(fixedDelay) with Spring 3.0 expression language?
...ationBean.stringValue}"/>
</task:scheduled-tasks>
... or if the cast from String to Long didn't work, something like this would:
<task:scheduled-tasks scheduler="myScheduler">
<task:scheduled ref="someObject" method="readLog"
fixed-rate="#{T(java.lang.Long).value...
Why would anybody use C over C++? [closed]
...en asked for, it is otherwise the same as C. (virtual, try/throw, dynamic_cast). Much of the overhead only shows in program image size.
– Zan Lynx
Feb 3 '09 at 1:41
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