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Group by in LINQ
... select new { PersonId = g.Key, Cars = g.ToList() };
Or as a non-query expression:
var results = persons.GroupBy(
p => p.PersonId,
p => p.car,
(key, g) => new { PersonId = key, Cars = g.ToList() });
Basically the contents of the group (when viewed as an IEnumerable<T&g...
Join a list of items with different types as string in Python
...d only convert the integers to strings when you need to display them. For example, if you have a list of integers then you can convert them one by one in a for-loop and join them with ,:
print(','.join(str(x) for x in list_of_ints))
...
Reorder levels of a factor without changing order of values
.... But this works: reorder(df$letters, seq(4,1))
– Alex Holcombe
Aug 29 '15 at 22:05
1
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Are static class variables possible in Python?
...it possible to have static class variables or methods in Python? What syntax is required to do this?
21 Answers
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Algorithm to calculate the number of divisors of a given number
...ms in the list instead of returning them however.
Here's a Dr. Math that explains what exactly it is you need to do mathematically.
Essentially it boils down to if your number n is:
n = a^x * b^y * c^z
(where a, b, and c are n's prime divisors and x, y, and z are the number of times that divisor ...
Scala Doubles, and Precision
...nance can require rounding and also performance.
– Rex Kerr
Jun 19 '12 at 20:33
28
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不到20个积木块，我用App Inventor 2给女儿做了个接星星小游戏 - App应用开...
...：
1. 一个Canvas（设置宽为"填充父容器"，高为400px，背景色为深蓝色）
2. 一个ImageSprite（放到Canvas里面，设置图片为篮子素材，名称为"Basket"）
3. 一个Ball（放到Canvas里面，设置半径12px，填充色#FFD700金色，名称...
Change all files and folders permissions of a directory to 644/755
...change all files to 644 and all folders to 755 using chmod from the linux command prompt? (Terminal)
8 Answers
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Android Center text on canvas
I'm trying to display a text using the code below.
The problem is that the text is not centered horizontally.
When I set the coordinates for drawText , it sets the bottom of the text at this position. I would like the text to be drawn so that the text is centered also horizontally.
...
How to install a previous exact version of a NPM package?
...ckage, just specify it
npm install <package>@<version>
For example: npm install express@3.0.0
You can also add the --save flag to that command to add it to your package.json dependencies, or --save --save-exact flags if you want that exact version specified in your package.json depen...