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Select first 4 rows of a data.frame in R
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Use head:
dnow <- data.frame(x=rnorm(100), y=runif(100))
head(dnow,4) ## default is 6
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How to monitor the memory usage of Node.js?
...ay of 10M elements consumers approximately 80MB (take a look at heapUsed).
If you look at V8's source code (Array::New, Heap::AllocateRawFixedArray, FixedArray::SizeFor), then you'll see that the memory used by an array is a fixed value plus the length multiplied by the size of a pointer. The latter...
How to disable admin-style browsable interface of django-rest-framework?
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'rest_framework.permissions.IsAuthenticatedOrReadOnly',
)
}
If you would like to completely hide the API unless the user is logged in, you could also use IsAuthenticated.
FYI: This will also remove the form from the HTML browseable API as it responds to permissions. When an authentic...
How to get the latest tag name in current branch in Git?
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This answer (and probably the others) runs into trouble if you have two tags pointing to the same commit. Unless the tags are annotated tags, I think there is no way for git to distinguish which of the two was created earlier.
– Paul Lynch
J...
Sharing src/test classes between modules in a multi-module maven project
...gin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<version>2.2</version>
<executions>
<execution>
<goals>
<goal>test-jar</goal>
</goals>
</execut...
Java reflection - impact of setAccessible(true)
... the accessibility back to its original state is not needed.
However...
If you want your calls to field.setAccessible(true) to be persistent you need to use underlying methods in java.lang.Class and java.lang.reflect.Field. The public facing methods send you copies of the Field instance, so it "f...
C# Pass Lambda Expression as Method Parameter
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@AdamLevitt - you can make the function generic, though if you want different numbers of parameters on the lambdas, you will need overloads.
– Oded
Jan 12 '13 at 20:35
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How to decompile an APK or DEX file on Android platform? [closed]
...eandroid.com/ from this web i able to decompile my code but both code are different why?
– Shailendr singh
Jun 2 '14 at 4:51
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Replace \n with actual new line in Sublime Text
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If this doesn't appear to be working, you might want to try replacing \n with your target string -- \\n replaces the actual sequence "\n" in the text content within your document, whereas \n replaces actual line breaks in the...
Converting pfx to pem using openssl
How to generate a .pem CA certificate and client certificate from a PFX file using OpenSSL.
3 Answers
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