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Extracting specific columns from a data frame
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how do I execute a further command onto this subset? E.g. I want to compute the rowMean: "df1 %>% rowMeans(select(A, B, E))" does not work.
– Ben
May 11 at 6:14
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Mailto links do nothing in Chrome but work in Firefox?
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I believe the default is to run the mail client on the computer. I know at work, it will run thunderbird; if they have outlook installed it may run outlook, etc. Personally, it did not run gmail by default, I had to set it up that way.
– kennypu
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Can't connect to local MySQL server through socket '/tmp/mysql.sock' (2)
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62
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Exclude .svn directories from grep [duplicate]
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37
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Check if a value exists in ArrayList
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Is there a version that compares object refferences?
– Tomáš Zato - Reinstate Monica
Feb 10 '15 at 22:37
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For..In loops in JavaScript - key value pairs
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If you can use ES6 natively or with Babel (js compiler) then you could do the following:
const test = {a: 1, b: 2, c: 3};
for (const [key, value] of Object.entries(test)) {
console.log(key, value);
}
Which will print out this output:
a 1
b 2
c 3
The...
Inserting a tab character into text using C#
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454
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Set the layout weight of a TextView programmatically
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97
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Bad class file magic or version
...y JAVA_HOME variable changed to Java 1.8 and I got this error message when compiling a pure java module as a dependency of my android project.
build.gradle of the java module
apply plugin: 'java'
Solution #1: Quick an dirty
I fixed it by setting my JAVA_HOME back to 1.7:
export JAVA_HOME=`/usr...
What is the difference between substr and substring?
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Sounds like a common source of error. Good to know the difference. Found additional comments about this here: rapd.wordpress.com/2007/07/12/javascript-substr-vs-substring
– schnaader
Sep 19 '10 at 11:...