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Create list of single item repeated N times
...
Create List of Single Item Repeated n Times in Python
Immutable items
For immutable items, like None, bools, ints, floats, strings, tuples, or frozensets, you can do it like this:
[e] * 4
Note that this is best only used with immutable items (strings, tuples, frozensets, ) in th...
How do I list all cron jobs for all users?
... by hour and minute, insert the
# header line, and format the results as a table.
cat "${temp}" |
sed --regexp-extended "s/^(\S+) +(\S+) +(\S+) +(\S+) +(\S+) +(\S+) +(.*)$/\1\t\2\t\3\t\4\t\5\t\6\t\7/" |
sort --numeric-sort --field-separator="${tab}" --key=2,1 |
sed "1i\mi\th\td\tm\tw\tus...
Why does Math.Round(2.5) return 2 instead of 3?
...5,MidpointRounding.AwayFromZero)" becoming 3).
The following diagram and table may help:
-3 -2 -1 0 1 2 3
+--|------+---------+----|----+--|------+----|----+-------|-+
a b c d e
...
In PHP what does it mean by a function being binary-safe?
...on. See: PHP strings
0x00 = NULL
0x04 = EOT (End of transmission)
ASCII table to see ASCII char list
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What's the difference between JPA and Spring Data JPA?
...ager, and annotations that help you map a Java entity object to a database table.
There are several JPA providers, like HIbernate, EclipseLink, or Open JPA which you can use.
Spring Data JPA
Spring Data JPA is a JPA data access abstraction. Just like JPA, Spring Data JPA cannot work without a JPA...
How to set a Django model field's default value to a function call / callable (e.g., a date relative
...ow_add=True in the constructor, the datetime referenced by my_date is "immutable" (only set once when the row is inserted to the table).
With auto_now=True, however, the datetime value will be updated every time the object is saved.
This was definitely a gotcha for me at one point. For reference, ...
Good reasons NOT to use a relational database?
...upport for versioning of data
Berkeley DB (Basically, a disk based hashtable)
Very simple conceptually (just un-typed key/value)
Quite fast
No administration overhead
Supports transactions I believe
Amazon's Simple DB
Much like Berkeley DB I believe, but hosted
Google's App Engine Da...
Difference between single and double quotes in Bash
...
The accepted answer is great. I am making a table that helps in quick comprehension of the topic. The explanation involves a simple variable a as well as an indexed array arr.
If we set
a=apple # a simple variable
arr=(apple) # an indexed array with a single e...
What is the difference between BIT and TINYINT in MySQL?
...thing on linux, I had problems with queries that inserted or selected from tables that had BIT DATA TYPE.
Bit is not safe for now.
I changed to tinyint(1) and worked perfectly. I mean that you only need a value to diferentiate if it's 1 or 0 and tinyint(1) it's ok for that
...
“On-line” (iterator) algorithms for estimating statistical median, mode, skewness, kurtosis?
...mate) mode and median calculation than gets easy, based on the frequencies table.
Normally Distributed Random Variables
If it is normally distributed, I would use the population sample mean, variance, skewness, and kurtosis as maximum likelihood estimators for a small subset. The (on-line) algorit...