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Are trailing commas in arrays and objects part of the spec?
...as just:
ObjectLiteral :
{ }
{ PropertyNameAndValueList }
For arrays literals (Section 11.1.4) it is even more interesting (Update: this already existed in ES3):
ArrayLiteral :
[ Elisionopt ]
[ ElementList ]
[ ElementList , Elision_opt ]
(where Elision_opt is Elisionopt, ...
Returning the product of a list
... # (4)
In the following configuration:
a = range(1, 101) # A
a = np.array(a) # B
a = np.arange(1, 1e4, dtype=int) #C
a = np.arange(1, 1e5, dtype=float) #D
Results with python 2.7.5
| 1 | 2 | 3 | 4 |
-------+-----------+-----------+-----------+---...
Creating dataframe from a dictionary where entries have different lengths
Say I have a dictionary with 10 key-value pairs. Each entry holds a numpy array. However, the length of the array is not the same for all of them.
...
How to remove line breaks (no characters!) from the string?
... str_replace() is by far faster than preg_replace()
$buffer = str_replace(array("\r", "\n"), '', $buffer);
Using less CPU power, reduces the world carbon dioxide emissions.
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Multiple linear regression in Python
...
The reg_m function is unnecessarily complicated. x = np.array(x).T, x = sm.add_constant(x) and results = sm.OLS(endog=y, exog=x).fit() is enough.
– cd98
Nov 14 '14 at 23:26
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How do I delete a fixed number of rows with sorting in PostgreSQL?
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Postgres docs recommend to use array instead of IN and subquery. This should work much faster
DELETE FROM logtable
WHERE id = any (array(SELECT id FROM logtable ORDER BY timestamp LIMIT 10));
This and some other tricks can be found here
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Java: Get last element after split
...e String split method and I want to have the last element.
The size of the Array can change.
12 Answers
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Appending to an object
...
How about storing the alerts as records in an array instead of properties of a single object ?
var alerts = [
{num : 1, app:'helloworld',message:'message'},
{num : 2, app:'helloagain',message:'another message'}
]
And then to add one, just use push:
alerts....
Swift make method parameter mutable?
...ide. In this case (x fits in register) there is virtually no cost. If x is array, struct, or object that is mutated, then a copy almost certainly needs to be performed (unless the optimizer can analyze it inline and alias it).
– wcochran
Apr 14 '17 at 16:00
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How do I set a variable to the output of a command in Bash?
...d y for port number:
{
read -u $list -a head # read header in array `head`
varnames=(${head[@]//[K1% -]}) # drop illegal chars for variable names
while read -u $list ${varnames[@],,} ;do
((pct=available*100/(available+used),pct<10)) &&
printf "WARN...