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To find whether a column exists in data frame or not
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11
To get the grepl a bit more precise, you could use grepl("^d$",names(dat)), to ensure that a column with name dd does not return TRUE.
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Regular expression \p{L} and \p{N}
...93C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4.61182 48.1414 4.61182C47.4335 4.61182 46.7256 4.91628 46.0943 5.50789C45.7307 4.9328 45.2525 4.66231 44.6595 4.66231C43.6264 4.66231 43.1481 5.28821 43.1481 6.59048V11.9512C43.1481 13.2535 43.6264 13.8962 44.6595 13.8962C45.69...
Disable ScrollView Programmatically?
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answered Apr 23 '11 at 11:09
Joseph EarlJoseph Earl
22.5k88 gold badges7373 silver badges8888 bronze badges
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How do I cast a string to integer and have 0 in case of error in the cast with PostgreSQL?
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Anthony BriggsAnthony Briggs
2,87511 gold badge1818 silver badges1212 bronze badges
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Selecting only first-level elements in jquery
...not the inner levels.
– Alfonso
Sep 11 '13 at 15:18
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Any way to break if statement in PHP?
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professorsloth
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answered Nov 15 '11 at 1:30
AgelessEssenceAgelessEssence
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How do I get a string format of the current date time, in python?
...-14_16:40:52.txt
2a: March 04, 2018
2b: March 04, 2018
3: Today is 2018-11-11 yay
Description:
Using the new string format to inject value into a string at placeholder {}, value is the current time.
Then rather than just displaying the raw value as {}, use formatting to obtain the correct da...
invalid command code ., despite escaping periods, using sed
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Community♦
111 silver badge
answered Oct 18 '13 at 19:02
damienfrancoisdamienfrancois
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How are echo and print different in PHP? [duplicate]
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From:
http://web.archive.org/web/20090221144611/http://faqts.com/knowledge_base/view.phtml/aid/1/fid/40
Speed. There is a difference between the two, but speed-wise it
should be irrelevant which one you use. echo is marginally faster
since it doesn't set a ret...
Handler is abstract ,cannot be instantiated
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Anand SaurabhAnand Saurabh
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