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How to get “wc -l” to print just the number of lines without file name?
outputs number of lines and file name.
9 Answers
9
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Split comma-separated strings in a column into separate rows
...odified according to Rich Scriven's comment,
Jaap's two data.table methods and two dplyr / tidyr approaches,
Ananda's splitstackshapesolution,
and two additional variants of Jaap's data.table methods.
Overall 8 different methods were benchmarked on 6 different sizes of data frames using the micro...
Android studio logcat nothing to show
I installed Android Studio yesterday, and I tried to use the LogCat to see the logs. But there is nothing to show in the logcat. I used the terminal to run ./adb logcat and it works.
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Calculate difference in keys contained in two Python dictionaries
Suppose I have two Python dictionaries - dictA and dictB . I need to find out if there are any keys which are present in dictB but not in dictA . What is the fastest way to go about it?
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Objective-C formatting string for boolean?
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Shouldn't the output strings be: "Yes" and "No" :P
– Ben S
Apr 8 '10 at 22:22
131
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Serializing object that contains cyclic object value
...beware of using, very potential crashes your app. needs correct semicolons and is not useable on event objects!
– Ol Sen
Apr 22 '13 at 16:07
3
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jQuery: what is the best way to restrict “number”-only input for textboxes? (allow decimal points)
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Update
There is a new and very simple solution for this:
It allows you to use any kind of input filter on a text <input>,
including various numeric filters. This will correctly handle
Copy+Paste, Drag+Drop, keyboard shortcuts, contex...
How to flatten tree via LINQ?
...er style", convert Flatten to a generic extension method that takes a tree and a function that produces descendants from a node:
public static IEnumerable<T> Flatten<T>(
this IEnumerable<T> e
, Func<T,IEnumerable<T>> f
) => e.SelectMany(c => f(c).Flatten(f)...
How can I generate random alphanumeric strings?
How can I generate a random 8 character alphanumeric string in C#?
33 Answers
33
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LINQ with groupby and count
...g>, where each Grouping itself exposes the Key used to create the group and also is an IEnumerable<T> of whatever items are in your original data set. You just have to call Count() on that Grouping to get the subtotal.
foreach(var line in data.GroupBy(info => info.metric)
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