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How to run Rake tasks from within Rake tasks?
I have a Rakefile that compiles the project in two ways, according to the global variable $build_type , which can be :debug or :release (the results go in separate directories):
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Replace a value in a data frame based on a conditional (`if`) statement
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Easier to convert nm to characters and then make the change:
junk$nm <- as.character(junk$nm)
junk$nm[junk$nm == "B"] <- "b"
EDIT: And if indeed you need to maintain nm as factors, add this in the end:
junk$nm <- as.factor(junk$nm)
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how can I Update top 100 records in sql server
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Sean
6,61733 gold badges2727 silver badges3030 bronze badges
answered Jul 29 '09 at 6:44
Umair AhmedUmair Ahmed
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Google Chrome form autofill and its yellow background
I have design problem with Google Chrome and its form autofill function.
If Chrome remembers some login/password it changes a background color to a yellow one.
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RegEx: Grabbing values between quotation marks
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I've been using the following with great success:
(["'])(?:(?=(\\?))\2.)*?\1
It supports nested quotes as well.
For those who want a deeper explanation of how this works, here's an explanation from user ephemient:
([""']) match a q...
psql: FATAL: role “postgres” does not exist
I'm a postgres novice.
18 Answers
18
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代码块超过1.2w编译apk报错问题 - App Inventor 2 中文网 - 清泛IT社区，为创新赋能！
报错信息：
3月 04, 2025 9:50:11 上午 com.google.appengine.tools.development.ApiProxyLocalImpl log
严重: javax.servlet.ServletContext log: Exception while dispatching incoming RPC call
com.google.gwt.user.server.rpc.UnexpectedException: Service method 'public abstract long com.google.appinv...
What file uses .md extension and how should I edit them?
On GitHub, several projects have README.md files. It seems like a simple format file to express text and pictures.
16 An...
What's the best way to build a string of delimited items in Java?
While working in a Java app, I recently needed to assemble a comma-delimited list of values to pass to another web service without knowing how many elements there would be in advance. The best I could come up with off the top of my head was something like this:
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Finding out whether a string is numeric or not
How can we check if a string is made up of numbers only. I am taking out a substring from a string and want to check if it is a numeric substring or not.
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