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Cron job every three days
Is it possible to run a cronjob every three days? Or maybe 10 times/month.
11 Answers
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How to avoid the “divide by zero” error in SQL?
... by zero" error we have programmed it like this:
Select Case when divisor=0 then null
Else dividend / divisor
End ,,,
But here is a much nicer way of doing it:
Select dividend / NULLIF(divisor, 0) ...
Now the only problem is to remember the NullIf bit, if I use the "/" key.
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Ruby on Rails and Rake problems: uninitialized constant Rake::DSL
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A tweet from DHH earlier. Rake .9.0 breaks Rails and several other things, you need to:
gem "rake", "0.8.7"
in your Gemfile.
share
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improve this answer
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How to create a UIView bounce animation?
...r alloc] initWithItems:@[self.redSquare]];
elasticityBehavior.elasticity = 0.7f;
[self.animator addBehavior:elasticityBehavior];
And here are the results
UIKit Dynamics is a really powerful and easy to use addition to iOS7 and you can get some great looking UI from it.
Other examples:
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Find the max of two or more columns with pandas
...df = pd.DataFrame({"A": [1,2,3], "B": [-2, 8, 1]})
>>> df
A B
0 1 -2
1 2 8
2 3 1
>>> df[["A", "B"]]
A B
0 1 -2
1 2 8
2 3 1
>>> df[["A", "B"]].max(axis=1)
0 1
1 8
2 3
and so:
>>> df["C"] = df[["A", "B"]].max(axis=1)
>>> df
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Random float number generation
...need to employ a more advanced method.
This will generate a number from 0.0 to 1.0, inclusive.
float r = static_cast <float> (rand()) / static_cast <float> (RAND_MAX);
This will generate a number from 0.0 to some arbitrary float, X:
float r2 = static_cast <float> (rand()) / ...
httpd: Could not reliably determine the server's fully qualified domain name, using 127.0.0.1 for Se
I tried to restart my Apache server on CentOS 5.0 and got this message:
11 Answers
11
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How to get a pixel's x,y coordinate color from an image?
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202
Building on Jeff's answer, your first step would be to create a canvas representation of your P...
New Array from Index Range Swift
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This works for me:
var test = [1, 2, 3]
var n = 2
var test2 = test[0..<n]
Your issue could be with how you're declaring your array to begin with.
EDIT:
To fix your function, you have to cast your Slice to an array:
func aFunction(numbers: Array<Int>, position: Int) -> Array&...
LINGO使用指南 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...：
在模型窗口中输入如下代码：
min=2*x1+3*x2;
x1+x2>=350;
x1>=100;
2*x1+x2<=600;
然后点击工具条上的按钮 即可。
例1.2 使用LINGO软件计算6个发点8个收点的最小费用运输问题。产销单位运价如下表。
销地
产地
B...