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filter for complete cases in data.frame using dplyr (case-wise deletion)
Is it possible to filter a data.frame for complete cases using dplyr? complete.cases with a list of all variables works, of course. But that is a) verbose when there are a lot of variables and b) impossible when the variable names are not known (e.g. in a function that processes any data.frame).
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GroupBy pandas DataFrame and select most common value
I have a data frame with three string columns. I know that the only one value in the 3rd column is valid for every combination of the first two. To clean the data I have to group by data frame by first two columns and select most common value of the third column for each combination.
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How does a Breadth-First Search work when looking for Shortest Path?
I've done some research, and I seem to be missing one small part of this algorithm. I understand how a Breadth-First Search works, but I don't understand how exactly it will get me to a specific path, as opposed to just telling me where each individual node can go. I guess the easiest way to explain...
Access denied for user 'root@localhost' (using password:NO)
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How do you make Vim unhighlight what you searched for? [duplicate]
I search for "nurple" in a file. I found it, great. But now, every occurrence of "nurple" is rendered in sick black on yellow. Forever.
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SQL RANK() versus ROW_NUMBER()
I'm confused about the differences between these. Running the following SQL gets me two idential result sets. Can someone please explain the differences?
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How can I open Java .class files in a human-readable way?
I'm trying to figure out what a Java applet's class file is doing under the hood. Opening it up with Notepad or Textpad just shows a bunch of gobbledy-gook.
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VIM Replace word with contents of paste buffer?
I need to do a bunch of word replacements in a file and want to do it with a vi command, not an EX command such as :%s///g . I know that this is the typical way one replaces the word at the current cursor position: cw<text><esc> but is there a way to do this with the contents of the u...
MySQL - Make an existing Field Unique
...ng table with a field that should be unique but is not. I only know this because an entry was made into the table that had the same value as another, already existing, entry and this caused problems.
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How to get the system uptime in Windows? [closed]
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