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How to optimize for-comprehensions and loops in Scala?
...
Now, in 2014, I tested this again and for me performance is the following: java -> 0.3s; scala -> 3.6s; scala optimized -> 3.5s; scala functional -> 4s; Looks much better than 3 years ago, but... Still th...
What is a None value?
...right and F = None resets F to its original state, then it should be there now, and we should see
>>> print(F)
None
like we do after we type F = None and put the sticker on None.
So that's all that's going on. In reality, Python comes with some stickers already attached to objects (b...
Generate all permutations of a list without adjacent equal elements
... cases, we find an optimal solution T that extends P', as needed.
Suppose now that P does end with y. Modify Q by moving the first occurrence of x to the front. In doing so, we introduce at most one defect (where x used to be) and eliminate one defect (the yy).
Generating all solutions
This is to...
What is the benefit of using Fragments in Android, rather than Views?
...loosing all images downloaded in that, so had to add cache implementation, now I'm thinking using fragments it may be very easy
– Shirish Herwade
Feb 9 '15 at 13:53
...
React JSX: selecting “selected” on selected option
...ange={this.handleChange} />
)
}
}
included component (which is now a stateless functional):
export const ReactExample = ({ name, value, handleChange }) => (
<select name={name} value={value} onChange={handleChange}>
<option value="A">Apple</option>
<opt...
Are there any O(1/n) algorithms?
...ensible when we take the mathematical definition of the Big O notation:
Now you can easily substitute g(x) for 1/x … it's obvious that the above definition still holds for some f.
For the purpose of estimating asymptotic run-time growth, this is less viable … a meaningful algorithm cannot ge...
How do I right align div elements?
...
@ShellNinja why? i know 0 is valid, however so is 0px... argue your point so we learn something.
– pstanton
Mar 17 '14 at 9:25
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Unit Testing AngularJS directive with templateUrl
...teCache. This solution is much less flexible, but it gets the job done for now.
// my-test.js
// Make template available to unit tests without Karma
//
// Disclaimer: Not using Karma may result in bad karma.
beforeEach(inject(function($templateCache) {
var directiveTemplate = null;
var req...
difference and when to use getApplication(), getApplicationContext(), getBaseContext() and someClass
...ctivity.this and getBaseContext, they all offer reference to the context.
Now the thing confuses is the declaration of different contexts and their specific-usage. To make things simple, you should count two types of context available in the Android framework.
Application Context
Activity Context...
Mean per group in a data.frame [duplicate]
..."Rate2"), row.names = c(NA, -9L), class = c("data.table", "data.frame"))
Now to take the mean of Rate1 and Rate2 for all 3 months, for each person (Name):
First, decide which columns you want to take the mean of
colstoavg <- names(mydt)[3:4]
Now we use lapply to take the mean over the column...