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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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Salting Your Password: Best Practices?

...chars and alphanumeric upper/lowercase. Extendable to say all hexadecimal strings under length Z (say 160) since I think a rainbow table of hashed hashes would be useful.. – Tom Ritter Mar 24 '09 at 13:51 ...
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Convert Set to List without creating new List

...ccepts a Collection as an argument, and your set is a Collection. List<String> mainList = new ArrayList<String>(); mainList.addAll(set); EDIT: as respond to the edit of the question. It is easy to see that if you want to have a Map with Lists as values, in order to have k different va...
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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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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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Efficient list of unique strings C#

What is the most efficient way to store a list of strings ignoring any duplicates? I was thinking a dictionary may be best inserting strings by writing dict[str] = false; and enumerating through the keys as a list. Is that a good solution? ...
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Check whether a string contains a substring

How can I check whether a given string contains a certain substring, using Perl? 3 Answers ...
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Why does Math.round(0.49999999999999994) return 1?

....printf("%016x\n", Double.doubleToLongBits(d)); } public static void main(String args[]) { double a = 0.5; double b = 0.49999999999999994; print(a); // 3fe0000000000000 print(b); // 3fdfffffffffffff print(a+b); // 3ff0000000000000 print(1.0); // 3ff000000000...
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NoSql Crash Course/Tutorial [closed]

... system that would use it or how I would implement it in my system. I'm really stuck in a relational-db mindset thinking of things in terms of tables and joins... ...
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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...