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How to Correctly Use Lists in R?
...dresses the question of the difference between [] and [[]].
In short [[]] selects a single item from a list and [] returns a list of the selected items. In your example, x = list(1, 2, 3, 4)' item 1 is a single integer but x[[1]] returns a single 1 and x[1] returns a list with only one value.
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How to Convert all strings in List to lower case using LINQ?
... So you'd want something like this:
List<string> lowerCase = myList.Select(x => x.ToLower()).ToList();
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How to create .pfx file from certificate and private key?
... simple.
Under the SSL tab, I first Imported the Certificate. Then once I selected the Certificate I was able to export as a PFX, both with and without a keyfile.
https://www.digicert.com/util
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How to insert a value that contains an apostrophe (single quote)?
... 'O''Brien')
/\
right here
The same applies to SELECT queries:
SELECT First, Last FROM Person WHERE Last = 'O''Brien'
The apostrophe, or single quote, is a special character in SQL that specifies the beginning and end of string data. This means that to use it as part...
How to access random item in list?
... isn't repeated? Let's say I wanted to shuffle a deck of cards by randomly selecting one at a time, but obviously can't select the same card twice.
– AdamMc331
Sep 21 '14 at 5:26
7...
mysql create user if not exists
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I use
SELECT EXISTS (SELECT DISTINCT user FROM mysql.user WHERE user = "username") as is_user
should return 1 if exists or 0 if it does not
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Can you resolve an angularjs promise before you return it?
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I think this answer should be selected.
– Morteza Tourani
May 8 '16 at 20:13
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Summarizing multiple columns with dplyr? [duplicate]
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I mean, the behavior like in select would be great: summarize(df, a:c, d=paste(d, collaspe =',' ) . Just want to put more original columns in for reference
– biocyberman
Aug 8 '15 at 17:28
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Is there a way to get colored text in Github Flavored Markdown? [duplicate]
...port { MovieService } from './services/movie.service';
@Component({
selector: 'app-root',
templateUrl: './app.component.html',
styleUrls: ['./app.component.css'],
providers: [ MovieService ]
})
export class AppComponent {
title = 'app works!';
}
```
No "pre" or "code...
How to get the date from jQuery UI datepicker
...tepicker_id').datepicker('getDate');
if (jsDate !== null) { // if any date selected in datepicker
jsDate instanceof Date; // -> true
jsDate.getDate();
jsDate.getMonth();
jsDate.getFullYear();
}
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