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Getting the count of unique values in a column in bash
I have tab delimited files with several columns. I want to count the frequency of occurrence of the different values in a column for all the files in a folder and sort them in decreasing order of count (highest count first). How would I accomplish this in a Linux command line environment?
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Is there a way of making strings file-path safe in c#?
My program will take arbitrary strings from the internet and use them for file names. Is there a simple way to remove the bad characters from these strings or do I need to write a custom function for this?
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How can I present a file for download from an MVC controller?
In WebForms, I would normally have code like this to let the browser present a "Download File" popup with an arbitrary file type, like a PDF, and a filename:
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Convert data.frame columns from factors to characters
I have a data frame. Let's call him bob :
18 Answers
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Split a string by another string in C#
I've been using the Split() method to split strings, but this only appears to work if you are splitting a string by a character. Is there a way to split a string , with another string being the split by parameter?
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How many threads can a Java VM support?
How many threads can a Java VM support? Does this vary by vendor? by operating system? other factors?
12 Answers
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Warning :-Presenting view controllers on detached view controllers is discouraged
In my app, I am using a navigation controller. Later on in some view I am using presentViewController for showing a zoomed image.
Also I am not using a Storyboard or nib.
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Convert java.util.Date to java.time.LocalDate
What is the best way to convert a java.util.Date object to the new JDK 8/JSR-310 java.time.LocalDate ?
13 Answers
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Programmatically align a toolbar on top of the iPhone keyboard
In several cases I want to add a toolbar to the top of the iPhone keyboard (as in iPhone Safari when you're navigating form elements, for example).
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How do I bind a WPF DataGrid to a variable number of columns?
My WPF application generates sets of data which may have a different number of columns each time. Included in the output is a description of each column that will be used to apply formatting. A simplified version of the output might be something like:
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