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Creating a new column based on if-elif-else condition
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To formalize some of the approaches laid out above:
Create a function that operates on the rows of your dataframe like so:
def f(row):
if row['A'] == row['B']:
val = 0
elif row['A'] > row['B']:
val = 1
else:
val = -1
return va...
How to list active / open connections in Oracle?
Is there any hidden table, system variable or something to show active connections in a given moment?
9 Answers
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What is the difference between class and instance attributes?
Is there any meaningful distinction between:
5 Answers
5
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Reshape three column data frame to matrix (“long” to “wide” format) [duplicate]
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There are many ways to do this. This answer starts with what is quickly becoming the standard method, but also includes older methods and various other methods from answers to similar questions scattered around this site.
tmp <- data.frame(x=gl(2,3, labels=letters[24:25]),
y...
PHP abstract properties
Is there any way to define abstract class properties in PHP?
9 Answers
9
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简单谈谈软件配置管理 - 项目管理 - 清泛网 - 专注C/C++及内核技术
...置项，建立和维护配置库；配置库管理；执行配置审计
b）配置控制委员会（CCB）：批准基线库的生成；评估和审核变更请求，并确保批准的更改得到实施.
c）QA：配置管理活动审查
2、配置管理的资源
a）配置库的服务器
b）...
Is Java's assertEquals method reliable?
...issues when comparing two Strings . It seems that String.equals() is a better approach. Well, I'm doing JUnit testing and my inclination is to use assertEquals(str1, str2) . Is this a reliable way to assert two Strings contain the same content? I would use assertTrue(str1.equals(str2)) , bu...
The ViewData item that has the key 'MY KEY' is of type 'System.String' but must be of type 'IEnumera
I am trying to populate a dropdown list from a database mapped with Linq-2-SQL, using ASP.NET MVC 2, and keep getting this error.
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What are free monads?
...een the term Free Monad pop up every now and then for some time, but everyone just seems to use/discuss them without giving an explanation of what they are. So: what are free monads? (I'd say I'm familiar with monads and the Haskell basics, but have only a very rough knowledge of category ...
How do I push to GitHub under a different username?
A friend and myself are sharing my computer. I've made pushes to GitHub using the git bash shell on Windows 7. Now we're in a different project on that computer and I need her to push to her account. But it keeps trying to use my username and saying I don't have access to her repository:
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