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what does the __file__ variable mean/do?
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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
...c(rep(c("A","B"), 50), rep(c("B","C"), each=25))
# Empty groups involving combinations of Species and group2 are not included in output
iris %>% group_by(Species, group2, .drop=FALSE) %>% tally
#> Species group2 n
#> 1 setosa A 25
#> 2 setosa B 25...
SignalR: Why choose Hub vs. Persistent Connection?
...erlaying the lower-level persistent connections.
From the highly up-voted comment below:
Partially correct. You can get topics or groups in persistent connections as well. The big difference is dispatching different types of messages. For example you have different kinds of messages and you wa...
Boolean operators && and ||
...f.
The functions all and any are often used on the result of a vectorized comparison to see if all or any of the comparisons are true, respectively. The results from these functions are sure to be length 1 so they are appropriate for use in if clauses, while the results from the vectorized comparis...
Detecting request type in PHP (GET, POST, PUT or DELETE)
...somewhat unfortunately named. $_GET contain variables from the URL's query component, regardless of the HTTP method. $_POST will contain form fields if the request was sent as application/x-www-form-urlencoded.
– Pj Dietz
Jul 23 '14 at 21:03
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What is the difference between JAX-RS and JAX-WS?
...lf. It's mostly that JAX-WS specification includes lots overhead in how it communicates.
On the point about WSDL and API definitions, REST will more frequently use the URI structure and HTTP commands to define the API rather than message types, as is done in the JAX-WS. This means that you don't n...
Can (domain name) subdomains have an underscore “_” in it?
...red name syntax" but read it carefully.
Domains with underscores are very common in the wild. Check _jabber._tcp.gmail.com or _sip._udp.apnic.net.
Other RFC mentioned here deal with different things. The original
question was for domain names. If the question is for host
names (or for URLs, which ...
Ruby: Merging variables in to a string
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How does a Linux/Unix Bash script know its own PID?
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Force point (“.”) as decimal separator in java
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