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Pass a data.frame column name to a function

... You can just use the column name directly: df <- data.frame(A=1:10, B=2:11, C=3:12) fun1 <- function(x, column){ max(x[,column]) } fun1(df, "B") fun1(df, c("B","A")) There's no need to use substitute, eval, etc. You can even pass the desired function as a parameter: fun1 <- function...
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How to open multiple pull requests on GitHub

... | edited Oct 27 '19 at 13:17 ahmednabil88 11.8k99 gold badges3939 silver badges7878 bronze badges ...
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How to get subarray from array?

I have var ar = [1, 2, 3, 4, 5] and want some function getSubarray(array, fromIndex, toIndex) , that result of call getSubarray(ar, 1, 3) is new array [2, 3, 4] . ...
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Difference between array_map, array_walk and array_filter

... preserve the keys. Example: <pre> <?php $origarray1 = array(2.4, 2.6, 3.5); $origarray2 = array(2.4, 2.6, 3.5); print_r(array_map('floor', $origarray1)); // $origarray1 stays the same // changes $origarray2 array_walk($origarray2, function (&$v, $k) { $v = floor($v); }); print_...
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Finding index of character in Swift String

... 32 Answers 32 Active ...
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What is the purpose and use of **kwargs?

... | edited Jul 29 '18 at 23:24 omkaartg 2,03811 gold badge66 silver badges2121 bronze badges ...
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What does the ^ operator do in Java?

... 422 The ^ operator in Java ^ in Java is the exclusive-or ("xor") operator. Let's take 5^6 as exam...
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Overloading Macro on Number of Arguments

I have two macros FOO2 and FOO3 : 8 Answers 8 ...
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Performance of foreach, array_map with lambda and array_map with static function

... 122 FWIW, I just did the benchmark since poster didn't do it. Running on PHP 5.3.10 + XDebug. UPD...
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SSH to Elastic Beanstalk instance

... I found it to be a 2-step process. This assumes that you've already set up a keypair to access EC2 instances in the relevant region. Configure Security Group In the AWS console, open the EC2 tab. Select the relevant region and click on Secur...