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ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.al
...understood way to evaluate
an array in boolean context: it could mean True if any element is
True, or it could mean True if all elements are True, or True if the array has non-zero length, just to name three possibilities.
Since different users might have different needs and different assumptions, ...
How can I have linebreaks in my long LaTeX equations?
...
If your equation does not fit on a single line, then the multline environment probably is what you need:
\begin{multline}
first part of the equation \\
= second part of the equation
\end{multline}
If you also need ...
Converting newline formatting from Mac to Windows
...
For anyone that comes across this now, the Homebrew formula is now called dos2unix. You'll want to brew install dos2unix.
– Geoff
Apr 26 '16 at 19:06
...
How do I set a conditional breakpoint in gdb, when char* x points to a string whose value equals “he
Can I specify that I want gdb to break at line x when char* x points to a string whose value equals "hello" ? If yes, how?
...
How to detect orientation change?
...on while using the camera with AVFoundation, and found that the didRotate (now deprecated) & willTransition methods were unreliable for my needs. Using the notification posted by David did work, but is not current for Swift 3.x/4.x.
Swift 4.2
The notification name has been changed.
The closure...
How to play with Control.Monad.Writer in haskell?
...Writer
ghci> let logNumber x = writer (x, ["Got number: " ++ show x])
Now logNumber is a function that creates writers. I can ask for its type:
ghci> :t logNumber
logNumber :: (Show a, MonadWriter [String] m) => a -> m a
Which tells me that the inferred type is not a function that r...
How to delete a file or folder?
..._path.mkdir()
file_path = directory_path / 'file'
file_path.touch()
and now:
>>> file_path.is_file()
True
Now let's delete them. First the file:
>>> file_path.unlink() # remove file
>>> file_path.is_file()
False
>>> file_path.exists()
False
We can use...
How can I visualize per-character differences in a unified diff file?
...y I get a patch created with git format-patch . The file is basically a unified diff with some metadata. If I open the file in Vim, I can see which lines have been modified, but I cannot see which characters in the changed lines differ. Does anyone know a way (in Vim, or some other free software ...
How to get all count of mongoose model?
How can I know the count of a model that data has been saved? there is a method of Model.count() , but it doesn't seem to work.
...
Ruby: How to turn a hash into HTTP parameters?
...re, considering all the major Ruby web frameworks are built on top of Rack now.
– iain
May 16 '13 at 13:10
@EdRuder Ac...