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Long list of if statements in Java

...void exec() { // ... } } // etc etc then build a Map<String,Command> object and populate it with Command instances: commandMap.put("A", new CommandA()); commandMap.put("B", new CommandB()); then you can replace your if/else if chain with: commandMap.get(value).exec(); ...
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Clear android application user data

...mission. So, run su first. Here is the sample code: private static final String CHARSET_NAME = "UTF-8"; String cmd = "pm clear com.android.browser"; ProcessBuilder pb = new ProcessBuilder().redirectErrorStream(true).command("su"); Process p = pb.start(); // We must handle the result stream in an...
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Converting string to numeric [duplicate]

...nt as.numeric to do with these values? In read.csv, try using the argument stringsAsFactors=FALSE Are you sure it's sep="/t and not sep="\t" Use the command head(pitchman) to check the first fews rows of your data Also, it's very tricky to guess what your problem is when you don't provide data. A mi...
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Is there any kind of hash code function in JavaScript?

... JavaScript objects can only use strings as keys (anything else is converted to a string). You could, alternatively, maintain an array which indexes the objects in question, and use its index string as a reference to the object. Something like this: var Ob...
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Start may not be called on a promise-style task. exception is coming

...s already started the task before giving it to you. You should only ever call Start on a task that you create by calling its constructor, and you shouldn't even do that unless you have a compelling reason to not start the task when you create it; if you want it started right away you should use Tas...
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Best way to represent a fraction in Java?

... 0x10000000000000L).) * * NOTE: In many cases, BigFraction(Double.toString(d)) may give a result * closer to what the user expects. */ public BigFraction(double d) { if(Double.isInfinite(d)) throw new IllegalArgumentException("double val is infinite"); if(Double.isNaN(...
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Filtering Pandas DataFrames on dates

...revious answer is not correct in my experience, you can't pass it a simple string, needs to be a datetime object. So: import datetime df.loc[datetime.date(year=2014,month=1,day=1):datetime.date(year=2014,month=2,day=1)] s...
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How to read a text file reversely with iterator in C#

...lt;/summary> public sealed class ReverseLineReader : IEnumerable<string> { /// <summary> /// Buffer size to use by default. Classes with internal access can specify /// a different buffer size - this is useful for testing. /// </summary> ...
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How does the HyperLogLog algorithm work?

...n be of different sizes. One element can be 1 another element "is this big string". So if you have a huge list (or a huge stream of elements) it will take a lot memory. Probabilistic Counting How can one get a reasonable estimate of a number of unique elements? Assume that you have a string of l...
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Printing object properties in Powershell

... Try this: Write-Host ($obj | Format-Table | Out-String) or Write-Host ($obj | Format-List | Out-String) share | improve this answer | follow ...