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Dynamically select data frame columns using $ and a character value
...itten as
`$`(df , V1)
or indeed
`$`(df , "V1")
But...
`$`(df , paste0("V1") )
...for instance will never work, nor will anything else that must first be evaluated in the second argument. You may only pass a string which is never evaluated.
Instead use [ (or [[ if you want to extract only...
SQL keys, MUL vs PRI vs UNI
...at column.
– pgoetz
Aug 7 '19 at 16:07
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How do I give text or an image a transparent background using CSS?
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30 Answers
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Numpy first occurrence of value greater than existing value
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207
This is a little faster (and looks nicer)
np.argmax(aa>5)
Since argmax will stop at the f...
How to validate an email address in PHP
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10 Answers
10
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How to make Twitter bootstrap modal full screen
...d this in Bootstrap 3 with the following code:
.modal-dialog {
width: 100%;
height: 100%;
margin: 0;
padding: 0;
}
.modal-content {
height: auto;
min-height: 100%;
border-radius: 0;
}
In general, when you have questions about spacing / padding issues, try right+clicking (or cmd+cl...
How can I confirm a database is Oracle & what version it is using SQL?
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10 Answers
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Two-dimensional array in Swift
...Int]] = []
OR if you need an array of predefined size (as mentioned by @0x7fffffff in comments):
// 2 dimensional array of arrays of Ints set to 0. Arrays size is 10x5
var arr = Array(count: 3, repeatedValue: Array(count: 2, repeatedValue: 0))
// ...and for Swift 3+:
var arr = Array(repeating: ...
Regex for string not ending with given suffix
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tckmntckmn
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Animation CSS3: display + opacity
...:hover .child
{
display: block;
-webkit-animation: fadeInFromNone 0.5s ease-out;
-moz-animation: fadeInFromNone 0.5s ease-out;
-o-animation: fadeInFromNone 0.5s ease-out;
animation: fadeInFromNone 0.5s ease-out;
}
@-webkit-keyframes fadeInFromNone {
0% {
display: no...