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Case objects vs Enumerations in Scala
...This is useful when wishing to persist enumerations (for example, to a database) or create them from data residing in files. However, I find in general that enumerations are a bit clumsy in Scala and have the feel of an awkward add-on, so I now tend to use case objects. A case object is more flexibl...
Expert R users, what's in your .Rprofile? [closed]
...he function (e.g. utils::head) otherwise it won't work.
# aliases
s <- base::summary
h <- utils::head
n <- base::names
EDIT: to answer your question, you can use the colorout package to have different colors in the terminal. Cool! :-)
...
What are the differences between the BLOB and TEXT datatypes in MySQL?
...(byte strings). They have no character set, and sorting and comparison are based on the numeric values of the bytes in column values.
TEXT values are treated as nonbinary strings (character strings). They have a character set, and values are sorted and compared based on the collation of the charact...
Semantic Diff Utilities [closed]
...h this scenario. Check http://www.semanticmerge.com
It merges (and diffs) based on code structure and not using text-based algorithms, which basically allows you to deal with cases like the following, involving strong refactor. It is also able to render both the differences and the merge conflicts ...
Does Haskell require a garbage collector?
...y integrated into the MLKit compiler. They experimented with purely region-based memory management (i.e. no garbage collector) as well as hybrid region-based/garbage-collected memory management, and reported that their test programs ran "between 10 times faster and 4 times slower" than pure garbage-...
Removing item from vector, while in C++11 range 'for' loop?
...
No, you can't. Range-based for is for when you need to access each element of a container once.
You should use the normal for loop or one of its cousins if you need to modify the container as you go along, access an element more than once, or ot...
CSS: fixed position on x-axis but not y?
...v class="position-fixed-y red-box">
</div>
The pattern of base pairs in the DNA double helix encodes the instructions for building the proteins necessary to construct an entire organism. DNA, or deoxyribonucleic acid, is found within most cells of an organism, and most organisms hav...
How do you configure Django for simple development and deployment?
...ings files.
settings_local.py - host-specific configuration, such as database name, file paths, etc.
settings_development.py - configuration used for development, e.g. DEBUG = True.
settings_production.py - configuration used for production, e.g. SERVER_EMAIL.
I tie these all together with a set...
Django Admin - Disable the 'Add' action for a specific model
...rgs):
form = super().get_form(request, obj, **kwargs)
form.base_fields['service'].widget.can_add_related = False
return form
In my case I use inline
# In inline formset e.g. admin.TabularInline
# disable all
def get_formset(self, request, obj=None, **kwargs):
f...
What is the difference between conversion specifiers %i and %d in formatted IO functions (*printf /
...haracters.
On the other hand for scanf there is a difference, %d assume base 10 while %i auto detects the base. We can see this by going to section 7.19.6.2 The fscanf function which covers scanf with respect to format specifier, in paragraph 12 it says:
The conversion specifiers and their me...