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Determine the number of NA values in a column
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If you are looking for NA counts for each column in a dataframe then:
na_count <-sapply(x, function(y) sum(length(which(is.na(y)))))
should give you a list with the counts for each column.
na_count <- data.frame(na_count)
Should output the data nicely in a dataframe like:
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Adding Only Untracked Files
...command:
git ls-files -o --exclude-standard | select | foreach { git add $_ }
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How to set the UITableView Section title programmatically (iPhone/iPad)?
... break;
}
return sectionName;
}
Swift
func tableView(_ tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
let sectionName: String
switch section {
case 0:
sectionName = NSLocalizedString("mySectionName", comment: "mySectio...
UnmodifiableMap (Java Collections) vs ImmutableMap (Google) [duplicate]
... edited Sep 24 '19 at 7:25
sP_
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answered Mar 25 '14 at 13:52
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Does the C++ standard mandate poor performance for iostreams, or am I just dealing with a poor imple
...ode compiled with GCC gives the following breakdown:
44.23% in std::basic_streambuf<char>::xsputn(char const*, int)
34.62% in std::ostream::write(char const*, int)
12.50% in main
6.73% in std::ostream::sentry::sentry(std::ostream&)
0.96% in std::string::_M_replace_safe(unsigned int, unsi...
How do I access my SSH public key?
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cat ~/.ssh/id_rsa.pub or cat ~/.ssh/id_dsa.pub
You can list all the public keys you have by doing:
$ ls ~/.ssh/*.pub
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How to make a phone call using intent in Android?
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You can use Intent.ACTION_DIAL instead of Intent.ACTION_CALL. This shows the dialer with the number already entered, but allows the user to decide whether to actually make the call or not. ACTION_DIAL does not require the CALL_PHONE permission.
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Convert Unix timestamp to a date string
...standard Perl solution is:
echo $TIMESTAMP | perl -nE 'say scalar gmtime $_'
(or localtime, if preferred)
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How to escape apostrophe (') in MySql?
...equences looks pretty similar.)
I think the Postgres note on the backslash_quote (string) parameter is informative:
This controls whether a quote mark can be represented by \' in a string literal. The preferred, SQL-standard way to represent a quote mark is by doubling it ('') but PostgreSQL ha...
Why does mongoose always add an s to the end of my collection name
...static get schema () {
var schema = mongoose.Schema({
_id : {
type: String
},
Name: {
type: String,
required: true
},
Age: {
type: Number,
required: tr...