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How to convert C# nullable int to int
...r are all correct; I just wanted to add one more that's slightly cleaner:
v2 = v1 ?? default(int);
Any Nullable<T> is implicitly convertible to its T, PROVIDED that the entire expression being evaluated can never result in a null assignment to a ValueType. So, the null-coalescing operator ?...
包默认：src\appinventor\ai_zqp2013\test269 定制包名考虑实现一下。 - 微...
包默认：src\appinventor\ai_zqp2013\test269
定制包名考虑实现一下。edu.mit.appinventor.aicompanion3.Screen1main=appinventor.ai_zqp2013.test269.Screen1
ai2starter46比aistarter改进的地方是什么 - App Inventor 2 中文网 - 清泛...
ai2starter46有什么优缺点，，还有什么地方是可以优化的
优点是它是最终的兜底方案，对于学生教学场景，功能测试要求不高、或不想受游戏App干扰、或商业模拟器安装不了，推荐使用AI2Starter模拟器。
缺点很明显，速度较慢...
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Simplest code for array intersection in javascript
... b.shift();
}
}
return result;
}
Non-destructive has to be a hair more complicated, since we’ve got to track indices:
/* finds the intersection of
* two arrays in a simple fashion.
*
* PARAMS
* a - first array, must already be sorted
* b - second array, must already be sort...
Cosine Similarity between 2 Number Lists
...e the nuts-and-bolts implementation:
import math
def cosine_similarity(v1,v2):
"compute cosine similarity of v1 to v2: (v1 dot v2)/{||v1||*||v2||)"
sumxx, sumxy, sumyy = 0, 0, 0
for i in range(len(v1)):
x = v1[i]; y = v2[i]
sumxx += x*x
sumyy += y*y
sumxy...
How do I finish the merge after resolving my merge conflicts?
...e merging branches. I quote this from the page https://git-scm.com/book/en/v2/Git-Branching-Basic-Branching-and-Merging
Git hasn’t automatically created a new merge commit. It has paused the process while you resolve the conflict. If you want to see which files are unmerged at any point after ...
API Versioning for Rails Routes
...espace :api do
namespace :v1 do
resources :users
end
namespace :v2 do
resources :users
end
match 'v:api/*path', :to => redirect("/api/v2/%{path}")
match '*path', :to => redirect("/api/v2/%{path}")
end
If your mind is still intact after this point, let me explain.
First,...
For each row return the column name of the largest value
...make examples using sample reproducible):
DF <- data.frame(V1=c(2,8,1),V2=c(7,3,5),V3=c(9,6,4))
colnames(DF)[apply(DF,1,which.max)]
[1] "V3" "V1" "V2"
A faster solution than using apply might be max.col:
colnames(DF)[max.col(DF,ties.method="first")]
#[1] "V3" "V1" "V2"
...where ties.method...
Download a specific tag with Git
...r checking out only a given tag for deployment, I use e.g.:
git clone -b 'v2.0' --single-branch --depth 1 https://github.com/git/git.git
This seems to be the fastest way to check out code from a remote repository if one has only interest in the most recent code instead of in a complete repository...