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PHP Foreach Pass by Reference: Last Element Duplicating? (Bug?)
... $item is still a reference to some value which is also being used by $arr[2]. So each foreach call in the second loop, which does not call by reference, replaces that value, and thus $arr[2], with the new value.
So loop 1, the value and $arr[2] become $arr[0], which is 'foo'.
Loop 2, the value and ...
Update multiple rows in same query using PostgreSQL
...zable:
update test as t set
column_a = c.column_a
from (values
('123', 1),
('345', 2)
) as c(column_b, column_a)
where c.column_b = t.column_b;
You can add as many columns as you like:
update test as t set
column_a = c.column_a,
column_c = c.column_c
from (values
('123...
C# equivalent to Java's charAt()?
...
201
You can index into a string in C# like an array, and you get the character at that index.
Exa...
Replace values in list using Python [duplicate]
...
207
Build a new list with a list comprehension:
new_items = [x if x % 2 else None for x in items]...
Passing a list of kwargs?
...f method(**kwargs):
print kwargs
keywords = {'keyword1': 'foo', 'keyword2': 'bar'}
method(keyword1='foo', keyword2='bar')
method(**keywords)
Running this in Python confirms these produce identical results:
{'keyword2': 'bar', 'keyword1': 'foo'}
{'keyword2': 'bar', 'keyword1': 'foo'}
...
What is the maven-shade-plugin used for, and why would you want to relocate Java packages?
...e to fall into a problem: A Qux project is depending on Foo, and also Bar:2.0 (and it cannot use Bar:1.0 because Qux needs to use new feature in Bar:2.0). Here is the dilemma: should Qux use Bar:1.0 (which Qux's code will not work) or Bar:2.0 (which Foo's code will not work)?
In order to solve th...
“ValueError: zero length field name in format” error in Python 3.0,3.1,3.2
...
I'm gonna guess that you are running python 2.6 by accident somehow.
This feature is only available for at least 3.1 if you are using python 3, or 2.7 if you are using python 2.
share
...
How to get the last N rows of a pandas DataFrame?
I have pandas dataframe df1 and df2 (df1 is vanila dataframe, df2 is indexed by 'STK_ID' & 'RPT_Date') :
3 Answers
...
How to use the 'sweep' function
...ation defined by FUN.
For instance, if you want to add 1 to the 1st row, 2 to the 2nd, etc. of the matrix you defined, you will do:
sweep (M, 1, c(1: 4), "+")
I frankly did not understand the definition in the R documentation either, I just learned by looking up examples.
...
How to get Scala List from Java List?
...
EDIT: Note that this is deprecated since 2.12.0. Use JavaConverters instead. (comment by @Yaroslav)
Since Scala 2.8 this conversion is now built into the language using:
import scala.collection.JavaConversions._
...
lst.toList.foreach{ node => .... }
works. ...