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How to find the sum of an array of numbers
...do know that this magic with reduce() is still 25-30% slower than a simple indexed for() loop after long years? jsperf.com/reduce-vs-loop/4
– tevemadar
Oct 29 '19 at 10:54
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Set Background cell color in PHPExcel
How to set specific color to active cell when creating XLS document in PHPExcel?
10 Answers
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Insert a row to pandas dataframe
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Just assign row to a particular index, using loc:
df.loc[-1] = [2, 3, 4] # adding a row
df.index = df.index + 1 # shifting index
df = df.sort_index() # sorting by index
And you get, as desired:
A B C
0 2 3 4
1 5 6 7
2 7 8 9
See in ...
Testing Abstract Classes
...ted, you need means to UT the concrete methods of abstract classes.
Personally, I use PHPUnit, and it has so called stubs and mock objects to help you testing this kind of things.
Straight from PHPUnit manual:
abstract class AbstractClass
{
public function concreteMethod()
{
retur...
How do I clone a range of array elements to a new array?
...ike to create a new array containing all the elements from X that begin at index 3 and ends in index 7. Sure I can easily write a loop that will do it for me but I would like to keep my code as clean as possible. Is there a method in C# that can do it for me?
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Access lapply index names inside FUN
Is there a way to get the list index name in my lapply() function?
12 Answers
12
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How to find largest objects in a SQL Server database?
...ize of indices and tables:
SELECT
t.name AS TableName,
i.name as indexName,
sum(p.rows) as RowCounts,
sum(a.total_pages) as TotalPages,
sum(a.used_pages) as UsedPages,
sum(a.data_pages) as DataPages,
(sum(a.total_pages) * 8) / 1024 as TotalSpaceMB,
(sum(a.used_pa...
difference between each.with_index and each_with_index in Ruby?
I'm really confused about the difference between each.with_index and each_with_index . They have different types but seem to be identical in practice.
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What is the meaning of “POSIX”?
... level
The Linux Standard Base further extends POSIX.
Use the non-frames indexes, they are much more readable and searchable: http://pubs.opengroup.org/onlinepubs/9699919799/nfindex.html
Get a full zipped version of the HTML pages for grepping: Where is the list of the POSIX C API functions?
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How can I define a composite primary key in SQL?
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SELECT * FROM voting WHERE QuestionID = 7
it will use the primary key's index. If however you do this:
SELECT * FROM voting WHERE MemberID = 7
it won't because to use a composite index requires using all the keys from the "left". If an index is on fields (A,B,C) and your criteria is on B and C...