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arrayfun can be significantly slower than an explicit loop in matlab. Why?
...ons to be vectorized 'column-wise'.
We can go back to Soln3 now. The loop order there is 'row-wise'. Lets change it
tic
Soln6 = ones(T, N);
for n = 1:N
for t = 1:T
Soln6(t, n) = 3*x(t, n)^2 + 2*x(t, n) - 1;
end
end
toc
Soln6 0.201661 seconds.
Better, but still very bad. Single ...
Adding new column to existing DataFrame in Python pandas
...
Super simple column assignment
A pandas dataframe is implemented as an ordered dict of columns.
This means that the __getitem__ [] can not only be used to get a certain column, but __setitem__ [] = can be used to assign a new column.
For example, this dataframe can have a column added to it by...
What is the purpose of @SmallTest, @MediumTest, and @LargeTest annotations in Android?
...x which is running tests.
Large: Accesses external file systems, networks, etc.
Per the Android Developers blog, a small test should take < 100ms, a medium test < 2s, and a large test < 120s.
See this page (search for "@SmallTest") on how to specify which tests get run.
...
What is the use of the square brackets [] in sql statements?
...be surrounded by brackets if you want to use them as column / table / sp / etc. names. In MySQL angled single quotes ```` would be the equivalent of this.
– Baz Guvenkaya
Feb 9 '17 at 5:03
...
How to stop text from taking up more than 1 line?
...ments" comment is right. If you try this in an anchor, paragraph, heading, etc, this does not work. You need to do something like p.oneline { white-space:nowrap; overflow:hidden; display:block;}
– Alex Angelico
May 11 '17 at 13:33
...
Media query to detect if device is touchscreen
...ery features.
if (Modernizr.touch){
// bind to touchstart, touchmove, etc and watch `event.streamId`
} else {
// bind to normal click, mousemove, etc
}
However, using CSS, there are pseudo class like, for example in Firefox. You can use :-moz-system-metric(touch-enabled). But these feature...
Array Size (Length) in C#
...ress the . key it shows you a list of all the methods, properties, events, etc. available on that object. When you highlight a member it gives you a brief description of what it does.
Press F1
If you find a method or property that might do what you want but you're not sure, you can move the curs...
Compiling/Executing a C# Source File in Command Prompt
...h knowledge of some sort of build tool such as NAnt, MSBuild, FinalBuilder etc. These tools provide a complete build environment, not just the basic compiler.
On a Mac
On a Mac, syntax is similar, only C sharp Compiler is just named csc:
$ csc /target:exe /out:MyApplication.exe MyApplication.cs ...
Adding a public key to ~/.ssh/authorized_keys does not log me in automatically
... be simple, but it hides some traps I'm trying to figure.
-- SERVER --
In /etc/ssh/sshd_config, set passwordAuthentication yes to let the server temporarily accept password authentication
-- CLIENT --
consider Cygwin as Linux emulation and install & run OpenSSH
1. Generate private and public k...
What does enumerable mean?
..., "valueOf", "hasOwnProperty", "isPrototypeOf", "propertyIsEnumerable", /* etc. */]
Each of these properties still exists on the object:
console.log('constructor' in foo); // true
console.log('toString' in foo); // true
// etc.
But, they're skipped by the for..in loop because they aren't enu...