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Test if characters are in a string
...unction
grepl(value, chars, fixed = TRUE)
# TRUE
Use ?grepl to find out more.
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Which HTML5 reset CSS do you use and why? [closed]
...TML5 reset CSS do you use and why? Is there one that you've found to cover more cases?
8 Answers
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Relational table naming convention [closed]
...ship is implemented in SQL as a CONSTRAINT FOREIGN KEY in the child table (more, later). Here is the Verb Phrase (in the model), the Predicate that it represents (to be read from the model), and the FK Constraint Name:
Initiates
Each Customer Initiates 0-to-n SalesOrders
Customer_Initi...
Is JavaScript an untyped language?
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Detect all changes to a (immediately) using JQuery
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PostgreSQL: How to make “case-insensitive” query
... suggest anyone just checking this should go with the accepted answer. See more details here and here
– Afolabi Olaoluwa Akinwumi
Dec 1 '16 at 19:35
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std::function and std::bind: what are they, and when should they be used?
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You can use std::bind to get g:
auto g = bind(f, _1, 4, _2);
This is more concise than actually writing a functor class to do it.
There are further examples in the article you link to. You generally use it when you need to pass a functor to some algorithm. You have a function or functor that ...
Fastest way to replace NAs in a large data.table
...set.seed(1)
dt1 = create_dt(2e5, 200, 0.1)
dim(dt1)
[1] 200000 200 # more columns than Ramnath's answer which had 5 not 200
f_andrie = function(dt) remove_na(dt)
f_gdata = function(dt, un = 0) gdata::NAToUnknown(dt, un)
f_dowle = function(dt) { # see EDIT later for more elegant solution...
How to “EXPIRE” the “HSET” child key in redis?
...se. This allows all those keys to fall in the same hash slot. You can read more about it here: https://redis.io/topics/cluster-tutorial
Now if we want to do the same operation of hashes, we could do:
HDEL hash_top_key child_key_1 => DEL {hash_top_key}child_key_1
HGET hash_top_key child_key_1 =...
How to recursively download a folder via FTP on Linux [closed]
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