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Append an object to a list in R in amortized constant time, O(1)?
... for(i in 1:n) {a <- list(a, list(i))}
},
by_index = {
a <- list(0)
for(i in 1:n) {a[length(a) + 1] <- i}
a
},
append_ = {
a <- list(0)
for(i in 1:n) {a <- append(a, i)}
...
Entity Framework: table without primary key
...nsert records ASAP. Having PK can be an issue when checking uniqueness and indexing happens. Also If your PK is IDENTITY so returning the generated value to the EF is another issue. using GUID instead? generation time and indexing/sorting is another issue!...SO IN some critical OLTP senarios(like Lo...
What is the difference between Ruby 1.8 and Ruby 1.9
...> ?c
=> "c"
Ruby 1.8.6
irb(main):001:0> ?c
=> 99
String index.
Ruby 1.9
irb(main):001:0> "cat"[1]
=> "a"
Ruby 1.8.6
irb(main):001:0> "cat"[1]
=> 97
{"a","b"} No Longer Supported
Ruby 1.9
irb(main):002:0> {1,2}
SyntaxError: (irb):2: syntax error, unexpecte...
How to initialize a private static const map in C++?
...ey,value> m1 = MyClass::getMyMap();
// then do work on m1 or
unsigned index = some predetermined value
MyClass::getMyMap().at( index ); // As long as index is valid this will
// retun map.second or map->second value so if in this case key is an
// unsigned and value is a std::string then...
What's the best way to set a single pixel in an HTML5 canvas?
...
function setPixel(imageData, x, y, r, g, b, a) {
var index = 4 * (x + y * imageData.width);
imageData.data[index+0] = r;
imageData.data[index+1] = g;
imageData.data[index+2] = b;
imageData.data[index+3] = a;
}
...
'git add --patch' to include new files?
...ng what git add -N does, it just adds the specified untracked files to the index, but without content.
– Odin
May 29 '19 at 0:17
...
What does “./” (dot slash) refer to in terms of an HTML file path location?
...
./ is the the folder that the working file is in:
So in /index.htm ./ is the root directory
but in /css/style.css ./ is the css folder.
This is important to remember because if you move CSS from /index.htm to /css/style.css the path will change.
...
Aborting a stash pop in Git
...y.
The reverse merge requires that all current changes be pushed into the index:
git add -u
Then invert the merge-recursive that was done by git stash apply:
git merge-recursive stash@{0}: -- $(git write-tree) stash@{0}^1
Now you will be left with just the non-stash changes. They will be i...
Getting an object from an NSSet
If you can't get an object with objectAtIndex: from an NSSet then how do you retrieve objects?
8 Answers
...
Retrieve a Fragment from a ViewPager
...ow. If using FragmentStatePagerAdapter its worth looking at this. Grabbing indexes that are not the current one in a FragmentStateAdapter is not as useful as by the nature of it these will be completely torn down went out of view / out of offScreenLimit bounds.
THE UNHAPPY PATHS
Wrong: Maintain yo...