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How to access maven.build.timestamp for resource filtering
I am using maven 3.0.4 and would like to make the build timestamp accessible to my application. For this, I'm putting a placeholder in a .properties file and let maven filter on build. While this is working fine for ${project.version} , ${maven.build.timestamp} is not substituted on filtering. ...
Replace all 0 values to NA
...me space for it. E.g.,
data.frame(x = c(1, NA, 2))
# x
# 1 1
# 2 NA
# 3 2
Also, the data frame structure requires all the columns to have the same number of elements so that there can be no "holes" (i.e., NULL values).
Now you could replace zeroes by NULL in a data frame in the sense of com...
Return type of '?:' (ternary conditional operator)
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3 Answers
3
Active
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Rails: How to list database tables/objects using the Rails console?
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308
You are probably seeking:
ActiveRecord::Base.connection.tables
and
ActiveRecord::Base.conn...
How do I interactively unstage a particular hunk in git?
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3 Answers
3
Active
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PHP foreach loop key value
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393
You can access your array keys like so:
foreach ($array as $key => $value)
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How to drop into REPL (Read, Eval, Print, Loop) from Python code
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answered Sep 8 '09 at 20:34
AlexAlex
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How to change the CHARACTER SET (and COLLATION) throughout a database?
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371
change database collation:
ALTER DATABASE <database_name> CHARACTER SET utf8 COLLATE utf...