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Select first 4 rows of a data.frame in R
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156
Use head:
dnow <- data.frame(x=rnorm(100), y=runif(100))
head(dnow,4) ## default is 6
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Can PostgreSQL index array columns?
...CREATE TABLE "Test"("Column1" int[]);
INSERT INTO "Test" VALUES ('{10, 15, 20}');
INSERT INTO "Test" VALUES ('{10, 20, 30}');
CREATE INDEX idx_test on "Test" USING GIN ("Column1");
-- To enforce index usage because we have only 2 records for this test...
SET enable_seqscan TO ...
How to add new item to hash
... the value !
– maguri
Apr 10 '18 at 15:15
3
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Get the client's IP address in socket.io
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edited Sep 25 '15 at 14:19
Balthazar
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RegEx backreferences in IntelliJ
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15
Seems like "\" is not required: jetbrains.com/idea/help/…. Also, for me it works only if I explicitly surround my group with "()", otherw...
Crontab Day of the Week syntax
...r Sat,Sun
– pkowalczyk
Dec 4 '17 at 15:33
Can you confirm this is case-insensitive? You switch a few times among SUN, ...
What does the “|” (single pipe) do in JavaScript?
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159
This is a bitwise or.
Since bitwise operations only make sense on integers, 0.5 is truncated.
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Sleeping in a batch file
...beard is outBlorgbeard is out
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How to do paging in AngularJS?
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edited Apr 8 '15 at 22:06
answered Jul 24 '13 at 15:24
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How can you find the unused NuGet packages in a solution?
...ve.
Unfortunately, this doesn't work for project.json projects (RSRP-454515) and ASP.NET core projects (RSRP-459076)
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