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How do I compute derivative using Numpy?
How do I calculate the derivative of a function, for example
8 Answers
8
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How to sum a variable by group
...
Using aggregate:
aggregate(x$Frequency, by=list(Category=x$Category), FUN=sum)
Category x
1 First 30
2 Second 5
3 Third 34
In the example above, multiple dimensions can be specified in the list. Multiple aggregated metrics of the same data type can be incorporated via cbind:
ag...
How can I change the language (to english) in Oracle SQL Developer?
... this option will be:
oracle.translated.locales = de,es,it,ja,ko,pt_BR,zh_CN,zh_TW
The original value was:
oracle.translated.locales = de,fr,es,it,ja,ko,pt_BR,zh_CN,zh_TW
The configuration above (sqldeveloper.conf file) will be wrong after remove french support and the french language does not...
How does the “this” keyword work?
...t("I'm evaluated in the initial global execution context!");
setTimeout(function () {
alert("I'm NOT evaluated in the initial global execution context.");
}, 1);
</script>
When evaluating code in the initial global execution context, ThisBinding is set to the global object, window ...
List all developers on a project in Git
...committer and author), you could use git log:
git log --pretty="%an %ae%n%cn %ce" | sort | uniq
%an author name
%ae author email
%n new line
%cn committer name
%ce committer email
Other placeholders are described in the pretty print documentation of git log.
...
Undefined, unspecified and implementation-defined behavior
...tandard as unspecified (for example, order of evaluation of arguments to a function). Where possible, this International Standard defines a set of allowable behaviors. These define the nondeterministic aspects of the abstract machine.
Certain other operations are described in this International Stan...
C++STL容器使用经验总结 - C/C++ - 清泛网 - 专注C/C++及内核技术
...ack(RCSPW(new Widget));
...
v.erase(remove_if(v.begin(),v.end(),not1(mem_fun(&Widget::isCertified))),v.end());
第34条：了解哪些算法要求使用排序的区间作为参数。
下面的代码要求排序的区间：
binary_search lower_bound
upper_bound equal_range
set_union set_...
https connection using CURL from command line
...ificate:
* subject: C=US; ST=California; L=Mountain View; O=Google Inc; CN=www.google.com
* start date: 2016-01-07 11:34:33 GMT
* expire date: 2016-04-06 00:00:00 GMT
* issuer: C=US; O=Google Inc; CN=Google Internet Authority G2
* SSL certificate verify ok.
* Server GFE/2.0 is not bla...
Load RSA public key from file
...ce;
}
/**
* Returns a CSR as string
* @param cn Common Name
* @param OU Organizational Unit
* @param Org Organization
* @param LocName Location name
* @param Statename State/Territory/Province/Region
* @param Country Country
*...
Should I Dispose() DataSet and DataTable?
... lot of folks use a using statement for IDisposables. using (SqlConnection cn = new SqlConnection(connectionString)) { using (SqlCommand cm = new SqlCommand(commandString, cn)) { cn.Open(); cm.ExecuteNonQuery(); } }
– DOK
May 19 '14 at 16:07
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