大约有 47,000 项符合查询结果(耗时:0.0738秒) [XML]
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...
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
...
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...
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...
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...
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?
...
Check whether a string contains a substring
How can I check whether a given string contains a certain substring, using Perl?
3 Answers
...
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...
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...
...
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...
