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detach all packages while working in R
...*) is not necessary but can be useful to prevent the NULL reply from vertically spamming the R window.
(edit: 9/20/2019) In version 3.6.1
It may be helpful to convert loaded only names(sessionInfo()$loadedOnly) to explicitly attached packages first, and then detach the packages, as so.
lapply(names(...
Python hashable dicts
...n algol-like language (as apposed to the syntax free lisp dialects you normally find them in). Because of this, different passes through the input might see different grammars, so cached parse results are invalid, unless I also store the current version of the grammar along with the cached parse re...
How to remove only underline from a:before?
...ntents of atomic inline-level descendants such as inline blocks and inline tables.
(Emphasis mine.)
Demo: http://jsfiddle.net/r42e5/10/
Thanks to @Oriol for providing the workaround that prompted me to check the specs and see that the workaround is legal.
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Rails: How do I create a default value for attributes in Rails activerecord's model? [duplicate]
... in the database. You can do this in your migrations. For example:
create_table :projects do |t|
t.string :status, :null => false, :default => 'P'
...
t.timestamps
end
Hope that helps.
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How to test Spring Data repositories?
...est the CrudRepo, the Entity and the DDL scripts which create the Entity's table(s).
– MirandaVeracruzDeLaHoyaCardina
Sep 25 '18 at 9:48
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How to downgrade or install an older version of Cocoapods
How can I downgrade Cocoapods to an older version, or how can I install an older version of Cocoapods?
6 Answers
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What is the most effective way for float and double comparison?
...
Be extremely careful using any of the other suggestions. It all depends on context.
I have spent a long time tracing a bugs in a system that presumed a==b if |a-b|<epsilon. The underlying problems were:
The implicit presumption in an algorithm that if a==b and b==c then a==c.
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Mapping enum to string in hibernate
... I was in hibernate.ddl-auto=update mode and I had to drop my table and let hibernate create it again in order to convert my enum from int to varchar. Hopefully it helps someone with similar issue.
– Arashsoft
Feb 15 '18 at 21:35
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How can I detect if the user is on localhost in PHP?
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Which would make this actually easier to break than spoofing the IP. You should really change it.
– Pekka
Jan 13 '10 at 0:09
3
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How to keep keys/values in same order as declared?
...his was achieved by using a simple array with integers for the sparse hash table, where those integers index into another array that stores the key-value pairs (plus the calculated hash). That latter array just happens to store the items in insertion order, and the whole combination actually uses le...