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How can I remove all objects but one from the workspace in R?
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require(gdata)
keep(object_1,...,object_n,sure=TRUE)
ls()
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Eclipse/Java code completion not working
... triggers for Java:
abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ._
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Getting raw SQL query string from PDO prepared statements
...= 1
You can also get what you want if you set the PDO attribute PDO::ATTR_EMULATE_PREPARES. In this mode, PDO interpolate parameters into the SQL query and sends the whole query when you execute(). This is not a true prepared query. You will circumvent the benefits of prepared queries by interp...
In bash, how does one clear the current input?
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Found a short reference at http://www.ice2o.com/bash_quick_ref.html while searching.
ctrl + e (if not at the end of the line) plus ctrl + u will do it.
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Nginx no-www to www and www to no-www
...separate server for example.org":
server {
listen 80;
server_name example.com;
return 301 http://www.example.com$request_uri;
}
server {
listen 80;
server_name www.example.com;
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}
HTTPS Solution
For those who want a solution including https://...
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Using Git with Visual Studio [closed]
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I usually add .user, *.suo, bin, obj, . and _* to my ignore list... if there's one of the above I want added, I can still add it manually.
– Tracker1
Mar 30 '11 at 0:17
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Change the font of a UIBarButtonItem
...Don't forget the exclamation mark (!) after the font. The error message: "'_' is not convertible to 'String'" is not really helpful.
– Ciryon
Sep 3 '15 at 6:41
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Difference between local and global indexes in DynamoDB
...s from the index, not from the base table.
– ethanxyz_0
Aug 8 '17 at 2:00
1
@bsd It would make se...
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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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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