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remove_if equivalent for std::map
...ments that needed to be erased.
This is a common algorithm I've seen used and documented in many places.
[EDIT] You are correct that iterators are invalidated after an erase, but only iterators referencing the element that is erased, other iterators are still valid. Hence using iter++ in the erase...
In Django, how do I check if a user is in a certain group?
...
then user.groups.all() returns [<Group: Editor>].
Alternatively, and more directly, you can check if a a user is in a group by:
if django_user.groups.filter(name = groupname).exists():
...
Note that groupname can also be the actual Django Group object.
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Javascript reduce() on Object
...u want the result as an Object ({ value: ... }), you'll have to initialize and return the object each time:
Object.keys(o).reduce(function (previous, key) {
previous.value += o[key].value;
return previous;
}, { value: 0 });
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Get UIScrollView to scroll to the top
...animated:YES];
or if you want to preserve the horizontal scroll position and just reset the vertical position:
[self.scrollView setContentOffset:CGPointMake(self.scrollView.contentOffset.x, 0)
animated:YES];
share
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Split delimited strings in a column and insert as new rows [duplicate]
...parate_rows function as described by @Tif below.
It works so much better, and it allows to "unnest" multiple columns in a single statement:
> head(mydf)
geneid chrom start end strand length gene_count
ENSG00000223972.5 chr1;chr1;chr1;chr1;chr1;chr1;chr1;chr1;chr1 11869;1...
Appending a vector to a vector [duplicate]
Assuming I have 2 standard vectors:
4 Answers
4
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How to show full object in Chrome console?
... It should be noted that just printing varName in Chrome console and hitting Enter gives the same effect as console.dir(varName).
– Vadzim
Oct 16 '17 at 14:58
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How do I save a String to a text file using Java?
...u would to any output stream:
out.println(text);
You'll need exception handling, as ever. Be sure to call out.close() when you've finished writing.
If you are using Java 7 or later, you can use the "try-with-resources statement" which will automatically close your PrintStream when you are done w...
Can't import my own modules in Python
I'm having a hard time understanding how module importing works in Python (I've never done it in any other language before either).
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How do I loop through a date range?
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A really nice solution for an interesting and real word problem. I like how this shows quite a few useful techniques of the language. And this reminds me that for loop is not only for (int i = 0;...) (-.
– Audrius
Dec 4 '09 at 1...