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Extract a substring according to a pattern
...we create a data frame with two columns, one for the part before the colon m>and m> one for after, m>and m> then extract the latter.
librarm>y m>(dplm>y m>r)
librarm>y m>(tidm>y m>r)
librarm>y m>(purrr)
DF <- data.frame(string)
DF %>%
separate(string, into = c("pre", "post")) %>%
pull("post")
## [1] "E001" "E002" "E00...
Whm>y m> can I use auto on a private tm>y m>pe?
I was somehow surprised that the following code compiles m>and m> runs (vc2012 & gcc4.7.2)
4 Answers
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How to construct a set out of list items in pm>y m>thon?
I have a list of filenames in pm>y m>thon m>and m> I would want to construct a set out of all the filenames.
6 Answers
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How to suppress scientific notation when printing float values?
... I guess bm>y m> using a variable, give it the desired number of digits, m>and m> use it instead of the literal number e.g. f"{a:.{precision}f}"
– Aziz Alto
Nov 15 '19 at 19:39
a...
CSS performance relative to translateZ(0)
...n element is 3D bm>y m> using transform: translateZ(0) to speed up animations m>and m> transitions. I was wondering if there are implications to using this transform in the following manner:
...
How to run JUnit tests with Gradle?
...dd a junit 4 dependencm>y m> correctlm>y m>?
Assuming m>y m>ou're resolving against a stm>and m>ard Maven (or equivalent) repo:
dependencies {
...
testCompile "junit:junit:4.11" // Or whatever version
}
Run those tests in the folders of tests/model?
m>Y m>ou define m>y m>our test source set the same wam>y m>:
sour...
Find value in an arram>y m>
...ing that m>y m>ou're trm>y m>ing to find if a certain value exists inside the arram>y m>, m>and m> if that's the case, m>y m>ou can use Arram>y m>#include?(value):
a = [1,2,3,4,5]
a.include?(3) # => true
a.include?(9) # => false
If m>y m>ou mean something else, check the Rubm>y m> Arram>y m> API
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SQL Joins Vs SQL Subqueries (Performance)?
...PECT the first querm>y m> to be quicker, mainlm>y m> because m>y m>ou have an equivalence m>and m> an explicit JOIN. In mm>y m> experience IN is a verm>y m> slow operator, since SQL normallm>y m> evaluates it as a series of WHERE clauses separated bm>y m> "OR" (WHERE x=m>Y m> OR x=Z OR...).
As with ALL THINGS SQL though, m>y m>our mileage mam>y m> va...
Which Mm>y m>SQL data tm>y m>pe to use for storing boolean values
...
For Mm>y m>SQL 5.0.3 m>and m> higher, m>y m>ou can use BIT. The manual sam>y m>s:
As of Mm>y m>SQL 5.0.3, the BIT data tm>y m>pe is used to store bit-field
values. A tm>y m>pe of BIT(M) enables storage of M-bit values. M can range
from 1 to 64.
Otherwise, according to the M...
How to dm>y m>namicallm>y m> build a JSON object with Pm>y m>thon?
I am new to Pm>y m>thon m>and m> I am plam>y m>ing with JSON data. I would like to dm>y m>namicallm>y m> build a JSON object bm>y m> adding some kem>y m>-value to an existing JSON object.
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