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Replace all 0 values to NA
...ays in ?'NULL',
NULL represents the null object in R
which is unique and, I guess, can be seen as the most uninformative and empty object.1 Then it becomes not so surprising that
data.frame(x = c(1, NULL, 2))
# x
# 1 1
# 2 2
That is, R does not reserve any space for this null object.2 Mea...
How to stop an animation (cancel() does not work)
...mation stop, it must remain in current position, i.e. I have sliding image and on touch event it must freeze on this place. clearAnimation() is not a case, because it resets state to start/end position depending on setFillAfter()
– Mix
Nov 6 '10 at 9:56
...
Check if a string is html or not
...se. If you use a < b && a > c the browser will turn the > and < characters into &gt; and &lt; entities appropriately. If, instead, you use a<b && a>c the browser will interpret the markup as a<b && a>c</b> because the lack of a space mean...
JPA eager fetch does not join
... JPA's fetch strategy control? I can't detect any difference between eager and lazy. In both cases JPA/Hibernate does not automatically join many-to-one relationships.
...
How can I find out the current route in Rails?
...ent_uri as "/my/test/path"
To find out the route i.e. controller, action and params:
path = ActionController::Routing::Routes.recognize_path "/your/path/here/"
# ...or newer Rails versions:
#
path = Rails.application.routes.recognize_path('/your/path/here')
controller = path[:controller]
action...
How to wait for all threads to finish, using ExecutorService?
...
Basically on an ExecutorService you call shutdown() and then awaitTermination():
ExecutorService taskExecutor = Executors.newFixedThreadPool(4);
while(...) {
taskExecutor.execute(new MyTask());
}
taskExecutor.shutdown();
try {
taskExecutor.awaitTermination(Long.MAX_VALUE,...
How do I read CSV data into a record array in NumPy?
...o a record array, much in the way that R's read.table() , read.delim() , and read.csv() family imports data to R's data frame?
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Meaning of epsilon argument of assertEquals for double values
... The documentation says, "delta - the maximum delta between expected and actual for which both numbers are still considered equal." So I think that should be a <= not <.
– Andrew Cheong
Apr 16 '18 at 17:00
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Fast way to discover the row count of a table in PostgreSQL
...IN pg_namespace n ON n.oid = c.relnamespace
WHERE c.relname = 'mytable'
AND n.nspname = 'myschema'
Or better still
SELECT reltuples::bigint AS estimate
FROM pg_class
WHERE oid = 'myschema.mytable'::regclass;
Faster, simpler, safer, more elegant. See the manual on Object Identifier Type...
When should I use a table variable vs temporary table in sql server?
...re details in table variable. It says that temp tables are always on disk, and table variables are in memory, that is to say, the performance of table variable is better than temp table because table variable uses less IO operations than temp table.
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