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Your content must have a ListView whose id attribute is 'android.R.id.list'
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345
Rename the id of your ListView like this,
<ListView android:id="@android:id/list"
andr...
Call apply-like function on each row of dataframe with multiple arguments from each row
...y to a subset of the original data.
dat <- data.frame(x=c(1,2), y=c(3,4), z=c(5,6))
apply(dat[,c('x','z')], 1, function(x) sum(x) )
or if your function is just sum use the vectorized version:
rowSums(dat[,c('x','z')])
[1] 6 8
If you want to use testFunc
testFunc <- function(a, b) a +...
How to check if array element exists or not in javascript?
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4
+1, nice. You can also use if(arrayName[index] === 'undefined') as a shortcut
– AnchovyLegend
Oct 8 '...
Use of def, val, and var in scala
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edited Apr 17 '11 at 4:46
Ying
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answered Dec 14 '10 at 15:...
Javascript reduce on array of objects
... the sum of the x properties of the parameters:
var arr = [{x:1},{x:2},{x:4}];
arr.reduce(function (a, b) {
return {x: a.x + b.x}; // returns object with property x
})
// ES6
arr.reduce((a, b) => ({x: a.x + b.x}));
// -> {x: 7}
Explanation added from comments:
The return value of each...
How do you reverse a string in place in JavaScript?
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answered Jun 6 '09 at 4:34
belacquabelacqua
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How do I compare two strings in Perl?
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answered Jul 24 '09 at 1:34
Sinan ÜnürSinan Ünür
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Using git, how do I ignore a file in one branch but have it committed in another branch?
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84
This solution appears to work only for certain, patched versions of git. See a new answer poi...
How do I find all of the symlinks in a directory tree?
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edited Jun 4 '14 at 21:12
chris Frisina
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How to make lists contain only distinct element in Python? [duplicate]
... Mark ByersMark Byers
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