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Combine two or more columns in a dataframe into a new column with a new name
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.@thelatemail - This worked for me: paste(df$n,df$s,sep="-")
– Chetan Arvind Patil
Oct 6 '17 at 19:09
2
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How do I flush the cin buffer?
...read in and ignore everything until EOF. (you can also supply a second argument which is the character to read until (ex: '\n' to ignore a single line).
Also: You probably want to do a: std::cin.clear(); before this too to reset the stream state.
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Remove multiple whitespaces
I'm getting $row['message'] from a MySQL database and I need to remove all whitespace like \n \t and so on.
15 Answer...
Shell script to send email [duplicate]
I am on linux machine and I monitor a process usage. Most of the time I will be away from my system and I have access to internet on my device. So I planned to write a shell-script that can mail me the output of the process.
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iOS detect if user is on an iPad
... can run on the Retina iPad and everything but there needs to be one adjustment. I need to detect if the current device is an iPad. What code can I use to detect if the user is using an iPad in my UIViewController and then change something accordingly?
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How to change UIPickerView height
Is it possible to change the height of UIPickerView? Some applications seem to have shorter PickerViews but setting a smaller frame doesn't seem to work and the frame is locked in Interface Builder.
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How do I make a UITableViewCell appear disabled?
I know about UITableview: How to Disable Selection for Some Rows but Not Others and cell.selectionStyle = UITableViewCellSelectionStyleNone , but how do I make a cell (or any UIView for that matter) appear disabled (grayed-out) like below?
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How set background drawable programmatically in Android
... you refer to the source code of ContextCompat.getDrawable, it gives you something like this:
/**
* Return a drawable object associated with a particular resource ID.
* <p>
* Starting in {@link android.os.Build.VERSION_CODES#LOLLIPOP}, the returned
* drawable will be styled for the specif...
Call a function from another file?
...ecause file is one of Python's core modules, so I suggest you change the name of your file.
Note that if you're trying to import functions from a.py to a file called b.py, you will need to make sure that a.py and b.py are in the same directory.
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How do I “git blame” a deleted line?
git blame is great for modified and added lines, but how can I find when a line that existed in a specific previous commit was eventually deleted. I'm thinking bisect , but I was hoping for something handier.
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