大约有 40,000 项符合查询结果(耗时:0.0561秒) [XML]

https://stackoverflow.com/ques... 

How to use a dot “.” to access members of dictionary?

...ope to help you: class Map(dict): """ Example: m = Map({'first_name': 'Eduardo'}, last_name='Pool', age=24, sports=['Soccer']) """ def __init__(self, *args, **kwargs): super(Map, self).__init__(*args, **kwargs) for arg in args: if isinstance(arg, dict...
https://stackoverflow.com/ques... 

Difference between a theta join, equijoin and natural join

... yourself). ** I don't quite know what the result of SELECT * FROM table_expression; is. I know it is not a relation because, among other reasons, it can have columns with duplicate names or a column with no name. I know it is not a set because, among other reasons, the column order is significan...
https://stackoverflow.com/ques... 

Use numpy array in shared memory for multiprocessing

...not available anymore) and @Henry Gomersall's answers. You could use shared_arr.get_lock() to synchronize access when needed: shared_arr = mp.Array(ctypes.c_double, N) # ... def f(i): # could be anything numpy accepts as an index such another numpy array with shared_arr.get_lock(): # synchroniz...
https://stackoverflow.com/ques... 

Using variables inside a bash heredoc

...text in a variable. Name='Rich Ba$tard' dough='$$$dollars$$$' cat <<____HERE $Name, you can win a lot of $dough this week! Notice that \`backticks' need escaping if you want literal text, not `pwd`, just like in variables like \$HOME (current value: $HOME) ____HERE Demo: https://ideone.com/...
https://stackoverflow.com/ques... 

How to assign colors to categorical variables in ggplot2 that have stable mapping?

...er.pal(5,"Set1") names(myColors) <- levels(dat$grp) colScale <- scale_colour_manual(name = "grp",values = myColors) and then add the color scale onto the plot as needed: #One plot with all the data p <- ggplot(dat,aes(x,y,colour = grp)) + geom_point() p1 <- p + colScale #A second plo...
https://stackoverflow.com/ques... 

Enable access control on simple HTTP server

...mport sys class CORSRequestHandler (SimpleHTTPRequestHandler): def end_headers (self): self.send_header('Access-Control-Allow-Origin', '*') SimpleHTTPRequestHandler.end_headers(self) if __name__ == '__main__': test(CORSRequestHandler, HTTPServer, port=int(sys.argv[1]) if le...
https://stackoverflow.com/ques... 

Using Python's os.path, how do I go up one directory?

... os.path.abspath(os.path.join(os.path.dirname( __file__ ), '..', 'templates')) As far as where the templates folder should go, I don't know since Django 1.4 just came out and I haven't looked at it yet. You should probably ask another question on SE to solve that issue....
https://stackoverflow.com/ques... 

Is there a performance difference between a for loop and a for-each loop?

...g4j.Marker, org.apache.logging.log4j.Marker...); Code: 0: iconst_0 1: istore_2 2: aload_1 3: arraylength 4: istore_3 5: iload_2 6: iload_3 7: if_icmpge 29 10: aload_1 11: iload_2 12: aaload 13: astore 4 ...
https://stackoverflow.com/ques... 

Lodash - difference between .extend() / .assign() and .merge()

... An important difference seems to be that while _.merge returns a new merged object, _.extend mutates the destination object in-place, – letronje Feb 13 '15 at 9:31 ...
https://stackoverflow.com/ques... 

Extract substring in Bash

Given a filename in the form someletters_12345_moreleters.ext , I want to extract the 5 digits and put them into a variable. ...