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Render a string in HTML and preserve spaces and linebreaks
...As part of that I have a description (retrieved from a db) that has spaces and new lines. When it is rendered the new lines and spaces are ignored by the html. I would like to encode those spaces and new lines so that they aren't ignored.
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How to redirect and append both stdout and stderr to a file with Bash?
...left to right as follows:
>>file.txt: Open file.txt in append mode and redirect stdout there.
2>&1: Redirect stderr to "where stdout is currently going". In this case, that is a file opened in append mode. In other words, the &1 reuses the file descriptor which stdout currently us...
Benefits of using the conditional ?: (ternary) operator
What are the benefits and drawbacks of the ?: operator as opposed to the standard if-else statement. The obvious ones being:
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Get first and last day of month using threeten, LocalDate
I have a LocalDate which needs to get the first and last day of the month.
How do I do that?
10 Answers
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What is the purpose of base 64 encoding and why it used in HTTP Basic Authentication?
...pedia page for HTTP Basic Authentication:
While encoding the user name and password with the Base64 algorithm typically makes them unreadable by the naked eye, they are as easily decoded as they are encoded. Security is not the intent of the encoding step. Rather, the intent of the encoding is t...
Apply a function to every row of a matrix or a data frame
Suppose I have a n by 2 matrix and a function that takes a 2-vector as one of its arguments. I would like to apply the function to each row of the matrix and get a n-vector. How to do this in R?
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Check folder size in Bash
I'm trying to write a script that will calculate a directory size and if the size is less than 10GB, and greater then 2GB do some action. Where do I need to mention my folder name?
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How do I clone a Django model instance object and save it to the database?
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Just change the primary key of your object and run save().
obj = Foo.objects.get(pk=<some_existing_pk>)
obj.pk = None
obj.save()
If you want auto-generated key, set the new key to None.
More on UPDATE/INSERT here.
Official docs on copying model instances: h...
What is the difference between .*? and .* regular expressions?
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It is the difference between greedy and non-greedy quantifiers.
Consider the input 101000000000100.
Using 1.*1, * is greedy - it will match all the way to the end, and then backtrack until it can match 1, leaving you with 1010000000001.
.*? is non-greedy. * w...
Is there a Python function to determine which quarter of the year a date is in?
...ed to count from 1 instead;-).
Originally two answers, multiply upvoted and even originally accepted (both currently deleted), were buggy -- not doing the -1 before the division, and dividing by 4 instead of 3. Since .month goes 1 to 12, it's easy to check for yourself what formula is right:
fo...