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Why do I get “Pickle - EOFError: Ran out of input” reading an empty file?
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I would check that the file is not empty first:
import os
scores = {} # scores is an empty dict already
if os.path.getsize(target) > 0:
with open(target, "rb") as f:
unpickler = pickle.Unpickler(f)
# if file is not empty scores will be equal
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std::string to float or double
...to convert a string to a double.
You can do it with the stringstream or boost::lexical_cast but those come with a performance penalty.
Ahaha you have a Qt project ...
QString winOpacity("0.6");
double temp = winOpacity.toDouble();
Extra note:
If the input data is a const char*, QByteArray::to...
onSaveInstanceState () and onRestoreInstanceState ()
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Usually you restore your state in onCreate(). It is possible to restore it in onRestoreInstanceState() as well, but not very common. (onRestoreInstanceState() is called after onStart(), whereas onCreate() is called before onStart().
Use the put methods to store values in onSav...
Printing 1 to 1000 without loop or conditionals
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Compile time recursion! :P
#include <iostream>
template<int N>
struct NumberGeneration{
static void out(std::ostream& os)
{
NumberGeneration<N-1>::out(os);
os << N << std::endl;
}
};
template<>
struct NumberGener...
Go install fails with error: no install location for directory xxx outside GOPATH
... @RobertReiz while I share your frustration, I should point out that most other languages do in fact use these, but maybe they're not as visible. For example, Python (a language famous for its simplicity) has PYTHONHOME instead of GOROOT and PYTHONPATH instead of GOPATH. Even (GC)C has LIBRARY_...
What is that “total” in the very first line after ls -l? [closed]
... is freely modifiable with the
--block-size=<int> flag on ls, the POSIXLY_CORRECT=1 GNU
environment variable (to get 512-byte units), or the -k flag to force
1kB units.
physical_block_size is the OS dependent value of an internal block interface, which may or may not be connected to t...
Match two strings in one line with grep
...nswered Dec 20 '10 at 6:16
dheerosaurdheerosaur
11.6k66 gold badges2727 silver badges3030 bronze badges
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What does the NS prefix mean?
...don't mind if the accepted answer changes to one of the others (if that's possible - never checked that).
– Olaf Kock
Aug 8 '12 at 20:21
2
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How to obtain a Thread id in Python?
...ython docs on Thread.name say "name - A string used for identification purposes only. It has no semantics. Multiple threads may be given the same name. The initial name is set by the constructor."
– drevicko
Dec 4 '12 at 6:10
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How to install therubyracer gem on 10.10 Yosemite?
I don't manage to install therubyracer gem on Yosemite 10.10.
18 Answers
18
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