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Extract a substring according to a pattern

... sub to replace it with a colon first. For example, if the separator were _ then string <- sub("_", ":", string) c(read.dcf(textConnection(string))) ## [1] "E001" "E002" "E003" 7) separate 7a) Using tidyr::separate we create a data frame with two columns, one for the part before the colon and o...
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Execute command without keeping it in history [closed]

... This will prevent all commands from being logged. It's not what the questioner wants. – Noufal Ibrahim Dec 12 '11 at 11:07 ...
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What are the precise rules for when you can omit parenthesis, dots, braces, = (functions), etc.?

...can omit dot when using the prefix, infix and postfix notations -- the so called operator notation. While using the operator notation, and only then, you can omit the parenthesis if there is less than two parameters passed to the method. Now, the operator notation is a notation for method-call, whi...
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How to parse float with two decimal places in javascript?

I have the following code. I would like to have it such that if price_result equals an integer, let's say 10, then I would like to add two decimal places. So 10 would be 10.00. Or if it equals 10.6 would be 10.60. Not sure how to do this. ...
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How to capture no file for fs.readFileSync()?

... Basically, fs.readFileSync throws an error when a file is not found. This error is from the Error prototype and thrown using throw, hence the only way to catch is with a try / catch block: var fileContents; try { fileContents =...
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How do I see what character set a MySQL database / table / column is?

... This should be merged in the top answer. It really helped me. – beppe9000 Jan 14 '17 at 16:55 add a comment  |  ...
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String literals: Where do they go?

I am interested in where string literals get allocated/stored. 8 Answers 8 ...
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Objective-C parse hex string to integer

... I'm going with this method, way simpler (and potentially quicker) than allocating an nsscanner. – Chris Jun 1 '11 at 6:25 1 ...
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String comparison using '==' vs. 'strcmp()'

... @onur güngör Actually, this does answers the op's question, which is So is there any reason to use strcmp() ?, while Postfuturist's answer doesn't. Oh, hell... no one answer seemed to compile at once the use of strcmp(), the performance of =...
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Are Java static initializers thread safe?

I'm using a static code block to initialize some controllers in a registry I have. My question is therefore, can I guarantee that this static code block will only absolutely be called once when the class is first loaded? I understand I cannot guarantee when this code block will be called, I'm guessi...