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Getting time elapsed in Objective-C
...er to use Apple's function CACurrentMediaTime!
I also benchmarked the mach_timebase_info call and it takes approximately 19ns on my iPhone 6, so I removed the (not threadsafe) code which was caching the output of that call.
#include <mach/mach.h>
#include <mach/mach_time.h>
uint64_t g...
append new row to old csv file python
I am trying to add a new row to my old csv file. Basically, it gets updated each time I run the Python script.
7 Answers
...
How can I have linebreaks in my long LaTeX equations?
...can be precisely controlled. e.g.
\begin{align*}
x&+y+\dots+\dots+x_100000000\\
&+x_100000001+\dots+\dots
\end{align*}
which would line up the first plus signs of each line... but obviously, you can set the alignments wherever you like.
...
Is there a pattern for initializing objects created via a DI container
...
{
get { return this.runTimeParam; }
}
}
Notice how this allows us to protect the class' invariants by use of the readonly keyword. No smelly Initialize methods are necessary.
An IMyIntfFactory implementation may be as simple as this:
public class MyIntfFactory : IMyIntfFactory
{...
What's the most elegant way to cap a number to a segment? [closed]
...a-library" answer but just in case you're using Lodash you can use .clamp:
_.clamp(yourInput, lowerBound, upperBound);
So that:
_.clamp(22, -10, 10); // => 10
Here is its implementation, taken from Lodash source:
/**
* The base implementation of `_.clamp` which doesn't coerce arguments.
*
* ...
Why is a div with “display: table-cell;” not affected by margin?
...
Cause
From the MDN documentation:
[The margin property] applies to all elements except elements with
table display types other than table-caption, table and inline-table
In other words, the margin property is not applicable to display:table-cell elements.
Solution
Consider using the bo...
How to remove/delete a large file from commit history in Git repository?
I accidentally dropped a DVD-rip into a website project, then carelessly git commit -a -m ... , and, zap, the repo was bloated by 2.2 gigs. Next time I made some edits, deleted the video file, and committed everything, but the compressed file is still there in the repository, in history.
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Install Gem from Github Branch?
...
You don't need to build the gem locally. In your gemfile you can specify a github source with a ref, branch or tag.
gem 'rails', :git => "git://github.com/rails/rails.git", :ref => "4aded"
gem 'rails', :git => "git://github.com/rails/rails.git", :bra...
Pandas aggregate count distinct
...
How about either of:
>>> df
date duration user_id
0 2013-04-01 30 0001
1 2013-04-01 15 0001
2 2013-04-01 20 0002
3 2013-04-02 15 0002
4 2013-04-02 30 0002
>>> df.groupby("date").agg({"duration": np.sum, "use...
Does R have an assert statement as in python?
...ndition that will throw an error in your program. Here's an example:
Less_Than_8 = function(x) return(x < 8)
for (i in 1:10)
{
print(i)
stopifnot(Less_Than_8(i))
}
This will print the numbers 1 through 8, then print a message that says
Error: Less_Than_8(i) is not TRUE
It would be ni...