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Why is Java's SimpleDateFormat not thread-safe? [duplicate]
...sed by operations on DateFormat / SimpleDateFormat.
For example parse(..) calls calendar.clear() initially and then calendar.add(..). If another thread invokes parse(..) before the completion of the first invocation, it will clear the calendar, but the other invocation will expect it to be populate...
Resizing SVG in html?
...it's just XML), and look for something like this at the top:
<svg ... width="50px" height="50px"...
Erase width and height attributes; the defaults are 100%, so it should stretch to whatever the container allows it.
sh...
The entity cannot be constructed in a LINQ to Entities query
There is an entity type called Product that is generated by entity framework.
I have written this query
14 Answers
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How to check if APK is signed or “debug build”?
As far as I know, in android "release build" is signed APK. How to check it from code or does Eclipse has some kinda of secret defines?
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How to split a dos path into its components in Python
...separator. On Linux, normpath will simply assume that you have a directory called \1\2 and a file or directory inside it called 3.
– Vojislav Stojkovic
Apr 30 '18 at 22:03
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What is the difference between dict.items() and dict.iteritems() in Python2?
...an item or add a (k,v) pair in the dictionary, the view object can automatically change at the same time.)
$ python2.7
>>> d = {'one':1, 'two':2}
>>> type(d.items())
<type 'list'>
>>> type(d.keys())
<type 'list'>
>>>
>>>
>>> type(d...
Combine two or more columns in a dataframe into a new column with a new name
... already mentioned in comments by Uwe and UseR, a general solution in the tidyverse format would be to use the command unite:
library(tidyverse)
n = c(2, 3, 5)
s = c("aa", "bb", "cc")
b = c(TRUE, FALSE, TRUE)
df = data.frame(n, s, b) %>%
unite(x, c(n, s), sep = " ", remove = FALSE)
...
Tainted canvases may not be exported
...mage data from localStorage instead of loading from file or any url, then did some manipulation to it like adding a text. Then tried to sotre back it to localStorage using toDataURL(). But it shows "Failed to execute 'toDataURL' on 'HTMLCanvasElement': Tainted canvases may not be exported". In this ...
In PHP, what is a closure and why does it use the “use” identifier?
...his is not evil at all and in fact it is quite powerful and useful.
Basically what this means is that you are allowing the anonymous function to "capture" local variables (in this case, $tax and a reference to $total) outside of it scope and preserve their values (or in the case of $total the ref...
How to lose margin/padding in UITextView?
...ing on scrollEnabled means "make this view expand as much as possible vertically," so it will add a huge margin at the bottom.)
Some further issues
(1) In some very unusual cases dynamically changing heights, Apple does a bizarre thing: they add extra space at the bottom.
No, really! This would hav...