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How do you extract a column from a multi-dimensional array?
...t;> A[:,2] # returns the third columm
array([3, 7])
See also: "numpy.arange" and "reshape" to allocate memory
Example: (Allocating a array with shaping of matrix (3x4))
nrows = 3
ncols = 4
my_array = numpy.arange(nrows*ncols, dtype='double')
my_array = my_array.reshape(nrows, ncols)
...
When should I use C++14 automatic return type deduction?
... work.
As a real-world example, I was asked to change a module from using raw pointers everywhere to smart pointers. Fixing the unit tests was more painful than the actual code.
While there are other ways this could be handled, the use of auto return types seems like a good fit.
...
How do I discover memory usage of my application in Android?
...system to this point.
Going lower-level, you can use the Debug API to get raw kernel-level information about memory usage: android.os.Debug.MemoryInfo
Note starting with 2.0 there is also an API, ActivityManager.getProcessMemoryInfo, to get this information about another process: ActivityManager.g...
What are the most interesting equivalences arising from the Curry-Howard Isomorphism?
... twist on this! In a language with parametric polymorphism, type variables range over all possible types, including uninhabited ones, so a fully polymorphic type such as ∀a. a is, in some sense, almost-false. So what if we write double almost-negation by using polymorphism? We get a type that look...
SQL statement to get column type
... this is great - but is it possible to also have it return the range for column's type? i.e. varchar(255) instead of varchar and int(11) instead of int ?
– Don Cheadle
Jun 29 '15 at 18:00
...
Rounding float in Ruby
... 0
raise ArgumentError, "#{p} is an invalid precision level. Valid ranges are integers > 0." unless p.class == Fixnum or p < 0
# Special case for 0 precision so it returns a Fixnum and thus doesn't have a trailing .0
return self.round if p == 0
# Standard case ...
Change drawable color programmatically
...ou might prefer PorterDuff.Mode.SRC_IN if you want it to work with a wider range of source colors.
– Lorne Laliberte
Jul 16 '15 at 19:27
1
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How to create an android app using HTML 5
...ing for UI Frameworks that can be used to build such apps, there is a wide range of different libraries. (Like Sencha, jQuery mobile, ...)
And to be a little biased, there is something I built as well: http://www.m-gwt.com
...
What's the right way to pass form element state to sibling/parent elements?
...n your situation.
If the app is a simple Markdown converter, C1 being the raw input and C2 being the HTML output, it's OK to let C1 trigger a setState in P, but some might argue this is not the recommended way to do it.
However, if the app is a todo list, C1 being the input for creating a new todo...
Why are joins bad when considering scalability?
...atabase used well. There are a number of scalability-friendly ways to take raw joins and make them much faster:
Join on a surrogate key (autonumer/identity column) rather than a natural key. This means smaller (and therefore faster) comparisons during the join operation
Indexes
Materialized/indexed...