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How can I remove all objects but one from the workspace in R?
I have a workspace with lots of objects and I would like to remove all but one. Ideally I would like to avoid having to type rm(obj.1, obj.2... obj.n) . Is it possible to indicate remove all objects but these ones ?
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Anonymous method in Invoke call
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Because Invoke/BeginInvoke accepts Delegate (rather than a typed delegate), you need to tell the compiler what type of delegate to create ; MethodInvoker (2.0) or Action (3.5) are common choices (note they have the same signature); like so:
control.Invoke...
How can I open Java .class files in a human-readable way?
I'm trying to figure out what a Java applet's class file is doing under the hood. Opening it up with Notepad or Textpad just shows a bunch of gobbledy-gook.
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Using scp to copy a file to Amazon EC2 instance?
I am trying to use my Mac Terminal to scp a file from Downloads (phpMyAdmin I downloaded online) to my Amazon EC2 instance.
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Could not load NIB in bundle
I am trying to integrate Janrain Engage as custom module with Appcelerator Titanium. I have created a sample module and dragged the JREngage folder to the sample module xcodeproj as indicated in the Jainrain's documentation.
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for each loop in Objective-C for accessing NSMutable dictionary
...tuff
}
This works for every class that conforms to the NSFastEnumeration protocol (available on 10.5+ and iOS), though NSDictionary is one of the few collections which lets you enumerate keys instead of values. I suggest you read about fast enumeration in the Collections Programming Topic.
Oh, I ...
How to print a float with 2 decimal places in Java?
Can I do it with System.out.print ?
16 Answers
16
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Can I grep only the first n lines of a file?
I have very long log files, is it possible to ask grep to only search the first 10 lines?
12 Answers
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Is There a Better Way of Checking Nil or Length == 0 of a String in Ruby?
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When I'm not worried about performance, I'll often use this:
if my_string.to_s == ''
# It's nil or empty
end
There are various variations, of course...
if my_string.to_s.strip.length == 0
# It's nil, empty, or just whitespace
end
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How to select only date from a DATETIME field in MySQL?
I have a table in the MySQL database that is set up with DATETIME . I need to SELECT in this table only by DATE and excluding the time.
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