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Understanding the Gemfile.lock file
After running the bundle install command, 'Gemfile.lock ' is created in the working directory. What do the directives inside that file mean?
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How to create a printable Twitter-Bootstrap page
... type="text/css" media="print" href="print.css">
or one you share for all devices:
<link rel="stylesheet" type="text/css" href="bootstrap.min.css"> # Note there's no media attribute
Then, you can write your styles for printers in the separate stylesheets or in the shared one using medi...
How to wait for all goroutines to finish without using time.Sleep?
This code selects all xml files in the same folder, as the invoked executable and asynchronously applies processing to each result in the callback method (in the example below, just the name of the file is printed out).
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How to call a Python function from Node.js
... have a machine learning algorithm to use in Python. Is there a way I can call Python functions from my Node.js application to make use of the power of machine learning libraries?
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count the frequency that a value occurs in a dataframe column
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If you want to apply to all columns you can use:
df.apply(pd.value_counts)
This will apply a column based aggregation function (in this case value_counts) to each of the columns.
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How to find the length of a string in R
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See ?nchar. For example:
> nchar("foo")
[1] 3
> set.seed(10)
> strn <- paste(sample(LETTERS, 10), collapse = "")
> strn
[1] "NHKPBEFTLY"
> nchar(strn)
[1] 10
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How do I test for an empty string in a Bash case statement?
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I use a simple fall through. no parameters passed ($1="") will be caught by the second case statement, yet the following * will catch any unknown parameter. Flipping the "") and *) will not work as *) will catch everything every time in that...
Why the switch statement cannot be applied on strings?
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The reason why has to do with the type system. C/C++ doesn't really support strings as a type. It does support the idea of a constant char array but it doesn't really fully understand the notion of a string.
In order to generate the code for a switch statement the compiler must under...
Difference between Activity and FragmentActivity
...compatibility with older versions of Android, but other than that, there really isn't much of a difference between the two. Just make sure you change all calls to getLoaderManager() and getFragmentManager() to getSupportLoaderManager() and getSupportFragmentManager() respectively.
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Control cannot fall through from one case label
...is present. I have the following code. But I am getting a "Control cannot fall through from one case label" error.
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