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How to get the primary IP address of the local machine on Linux and OS X? [closed]
... return me the primary (first) IP address of the localhost, other than 127.0.0.1
31 Answers
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Email Address Validation in Android on EditText [duplicate]
...target).
– rciovati
Apr 13 '13 at 9:02
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How can I convert a DateTime to the number of seconds since 1970?
...ateTime variable to Unix time, ie, the number of seconds since Jan 1st, 1970. It looks like a DateTime is actually implemented as the number of 'ticks' since Jan 1st, 0001.
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How to output only captured groups with sed?
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answered May 6 '10 at 2:39
Paused until further notice.Paused until further notice.
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Elastic Search: how to see the indexed data
...ing on your local machine), open a browser window to:
http://localhost:9200/_plugin/head/
Alternatively, you can just use curl from the command line, eg:
Check the mapping for an index:
curl -XGET 'http://127.0.0.1:9200/my_index/_mapping?pretty=1'
Get some sample docs:
curl -XGET 'http:...
How to run crontab job every week on Sunday
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10 Answers
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java.net.ConnectException: localhost/127.0.0.1:8080 - Connection refused
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10 Answers
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Is object empty? [duplicate]
...n-zero value
// that that property is correct.
if (obj.length > 0) return false;
if (obj.length === 0) return true;
// If it isn't an object at this point
// it is empty, but it can't be anything *but* empty
// Is it empty? Depends on your application.
if (typeof...
How to check whether a pandas DataFrame is empty?
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505
You can use the attribute df.empty to check whether it's empty or not:
if df.empty:
print(...
Convert column classes in data.table
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For a single column:
dtnew <- dt[, Quarter:=as.character(Quarter)]
str(dtnew)
Classes ‘d...