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How good is Java's UUID.randomUUID?
I know that randomized UUIDs have a very, very, very low probability for collision in theory, but I am wondering, in practice, how good Java's randomUUID() is in terms of not having collision? Does anybody have any experience to share?
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Iterate over model instance field names and values in template
... instance's field values, along with their names. Think of it as just a standard output of the values of that instance in table format, with the field name (verbose_name specifically if specified on the field) in the first column and the value of that field in the second column.
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Convert column classes in data.table
... dt[, Quarter:=as.character(Quarter)]
str(dtnew)
Classes ‘data.table’ and 'data.frame': 10 obs. of 3 variables:
$ ID : Factor w/ 2 levels "A","B": 1 1 1 1 1 2 2 2 2 2
$ Quarter: chr "1" "2" "3" "4" ...
$ value : num -0.838 0.146 -1.059 -1.197 0.282 ...
Using lapply and as.charac...
What are the best practices for JavaScript error handling?
I'm looking to start making my JavaScript a bit more error proof, and I'm finding plenty of documentation on using try , catch , finally , and throw , but I'm not finding a ton of advice from experts on when and where to throw errors.
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Step-by-step debugging with IPython
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You can use IPython's %pdb magic. Just call %pdb in IPython and when an error occurs, you're automatically dropped to ipdb. While you don't have the stepping immediately, you're in ipdb afterwards.
This makes debugging individual functions easy, as you can just load a file with %load...
__lt__ instead of __cmp__
...s ComparableMixin:
def __eq__(self, other):
return not self<other and not other<self
def __ne__(self, other):
return self<other or other<self
def __gt__(self, other):
return other<self
def __ge__(self, other):
return not self<other
def __le__(self, other):...
How can I use pointers in Java?
...have pointers, but I heard that Java programs can be created with pointers and that this can be done by the few who are experts in java. Is it true?
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What is the difference between Normalize.css and Reset CSS?
...ample, elements like sup or sub "just work" after including normalize.css (and are actually made more robust) whereas they are visually indistinguishable from normal text after including reset.css. So, normalize.css does not impose a visual starting point (homogeny) upon you. This may not be to ever...
Calculate age given the birth date in the format YYYYMMDD
... answered Feb 24 '14 at 9:51
André Snede KockAndré Snede Kock
8,41355 gold badges4040 silver badges6161 bronze badges
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detach all packages while working in R
...nly names(sessionInfo()$loadedOnly) to explicitly attached packages first, and then detach the packages, as so.
lapply(names(sessionInfo()$loadedOnly), require, character.only = TRUE)
invisible(lapply(paste0('package:', names(sessionInfo()$otherPkgs)), detach, character.only=TRUE, unload=TRUE, force...