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How to select the rows with maximum values in each group with dplyr? [duplicate]
I would like to select a row with maximum value in each group with dplyr.
6 Answers
6
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Android – Listen For Incoming SMS Messages
I am trying to create an application for monitoring incoming SMS messages, and launch a program via incoming SMS, also it should read the content from the SMS.
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How to display unique records from a has_many through relationship?
...From the Rails documentation:
:uniq
If true, duplicates will be omitted from the collection. Useful in conjunction with :through.
UPDATE FOR RAILS 4:
In Rails 4, has_many :products, :through => :orders, :uniq => true is deprecated. Instead, you should now write has_many :products, ...
What does Java option -Xmx stand for? [duplicate]
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see here: Java Tool Doc, it says,
-Xmxn
Specify the maximum size, in bytes, of the memory allocation pool. This value must a multiple of 1024 greater than 2MB. Append the letter k or K to indicate kilobytes, or m or M to indicate megabytes....
Set a persistent environment variable from cmd.exe
...ter the cmd window has been closed.
For example, to set an env var "foo" with value of "bar":
setx foo bar
Though it's worth reading the 'notes' that are displayed if you print the usage (setx /?), in particular:
2) On a local system, variables created or modified by this tool will be availa...
background function in Python
...that sometimes displays images to the user. The images can, at times, be quite large, and they are reused often. Displaying them is not critical, but displaying the message associated with them is. I've got a function that downloads the image needed and saves it locally. Right now it's run inline wi...
Remote Connections Mysql Ubuntu
... and assigned to your computers IP address and not loopback
#Replace xxx with your IP Address
bind-address = xxx.xxx.xxx.xxx
Or add a
bind-address = 0.0.0.0 if you don't want to specify the IP
Then stop and restart MySQL with the new my.cnf entry. Once running go to the terminal a...
Override configured user for a single git commit
I am trying to commit to a project on github.com from my work laptop, which is already configured for the company git server. Is there a way to commit specifying different author credentials, possible using a different configuration file or orther command line switches?
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Removing non-repository files with git?
I'm writing Autotools code and in the process of development, tons of files are generated.
1 Answer
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Get query from java.sql.PreparedStatement [duplicate]
... and MySQL 5.x JDBC drivers. For the case your JDBC driver doesn't support it, your best bet is using a statement wrapper which logs all setXxx() methods and finally populates a SQL string on toString() based on the logged information. For example Log4jdbc or P6Spy.
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