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Rails: Default sort order for a rails model?
...hen it gets used for actions like where's limiting (filtering) the default selection (a bad idea for a default) rather than just being used for ordering results.
For where selections, just use the regular named scopes. and add that scope on in the query, e.g. Book.all.published where published is a ...
Create list of single item repeated N times
...t that can be used to create a list if you wish! Let's try that again, but converting to a list:
>>> timeit.timeit('list(itertools.repeat(0, 10))', 'import itertools', number = 1000000)
1.7508119747063233
So if you want a list, use [e] * n. If you want to generate the elements lazily, us...
What's the difference between String(value) vs value.toString()
...cation, the [[DefaultValue]] internal operation.
Briefly summarized, when converting from Object-to-String, the following steps are taken:
If available, execute the toString method.
If the result is a primitive, return result, else go to Step 2.
If available, execute the valueOf method.
If t...
Creation timestamp and last update timestamp with Hibernate and MySQL
...
Correct. MySQL timestamp is always in UTC. MySQL converts TIMESTAMP values from the current time zone to UTC for storage, and back from UTC to the current time zone for retrieval. MySQL documentation: The DATE, DATETIME, and TIMESTAMP Types
– Ole V.V.
...
Mean per group in a data.frame [duplicate]
...0.33333
#3 Cat 2 44.66667 54.00000
Using data.table:
# At first, I convert the data.frame to data.table and then I group it
setDT(d)
d[, .(Rate1 = mean(Rate1), Rate2 = mean(Rate2)), by = .(Name)]
# Name Rate1 Rate2
#1: Aira 16.33333 47.00000
#2: Ben 31.33333 50.33333
#3: Cat 44.66...
How to set standard encoding in Visual Studio
...files comform to set rules. Note that Visual Studio does not automatically convert all your files but do its bit when you work with files in IDE (open and save).
What next
While you could have a Visual-studio-wide setup, I strongly suggest to still include an EditorConfig root to your solution ve...
What does “Content-type: application/json; charset=utf-8” really mean?
...", "UTF-8");) for me and I had to retrieve response data as draw bytes and convert it into String using UTF-8. So, it is recommended to be explicit and avoid assumption of default value.
share
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imp...
How do I change the formatting of numbers on an axis with ggplot?
... E.g.: (3x10^+2 -> 3x10^2) l <- gsub("e\\+","e",l) and after it: # convert 1x10^ or 1.000x10^ -> 10^ l <- gsub("\\'1[\\.0]*\\'\\%\\*\\%", "", l) to make it in format usually used in papers.
– John_West
Feb 23 '16 at 14:08
...
What's best SQL datatype for storing JSON string?
...is based on nvarchar) will be introduced, as well as a FOR JSON command to convert output from a query into JSON format
Update #2: in the final product, Microsoft did not include a separate JSON datatype - instead, there are a number of JSON-functions (to package up database rows into JSON, or to p...
How does the main() method work in C?
...stom-generate the __start function (or whatever it is called), or at least select one from several pre-compiled alternatives. Information could be stored in the object file about which of the supported forms of main is being used. The linker can look at this info, and select the correct version of ...