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How to take column-slices of dataframe in pandas
...e .loc
See the deprecation in the docs
.loc uses label based indexing to select both rows and columns. The labels being the values of the index or the columns. Slicing with .loc includes the last element.
Let's assume we have a DataFrame with the following columns:
foo, bar, quz, ant, cat, ...
Equivalent of *Nix 'which' command in PowerShell?
...or of giving you the path you'll need to pipe the output of get-command to select -expandproperty Path.
– Casey
Jul 29 '15 at 12:37
6
...
PostgreSQL LIKE query performance variations
... gist_trgm_ops);
Difference between GiST and GIN index
Example query:
SELECT * FROM tbl WHERE col LIKE '%foo%'; -- leading wildcard
SELECT * FROM tbl WHERE col ILIKE '%foo%'; -- works case insensitively as well
Trigrams? What about shorter strings?
Words with less than 3 letters in indexed...
LEFT OUTER joins in Rails 3
...OUTER JOIN users ON users.id = posts.user_id").
joins(:blog).select
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SQL Server - where is “sys.functions”?
... easy enough to roll your own:
CREATE VIEW my_sys_functions_equivalent
AS
SELECT *
FROM sys.objects
WHERE type IN ('FN', 'IF', 'TF') -- scalar, inline table-valued, table-valued
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Xcode 6 - How to pick signing certificate/provisioning profile for Ad-Hoc distribution?
...ple.com and find the distribution provisioning profile you want to use.
2) Select it, click "Edit", re-name the profile, and click "Generate".
3) Download the provisioning profile to the Desktop and drag it onto the Xcode 6 icon.
4) Re-start Xcode 6.
5) Open the organizer window and click "Submit" o...
Cannot install Lxml on Mac os x 10.9
... or upgrade the commandline tool for xcode.
Try this in a terminal:
xcode-select --install
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SQL left join vs multiple tables on FROM line?
...nts that have employees, but always list all companies.
So you do this:
SELECT * -- for simplicity
FROM Company, Department, Employee
WHERE Company.ID *= Department.CompanyID
AND Department.ID = Employee.DepartmentID
Note that the last one there is an inner join, in order to fulfill the crite...
How can I return pivot table output in MySQL?
...OUP BY.
The basic SQL providing this pivot can look something like this:
SELECT P.`company_name`,
COUNT(
CASE
WHEN P.`action`='EMAIL'
THEN 1
ELSE NULL
END
) AS 'EMAIL',
COUNT(
CASE
WHEN P.`action`='PRINT' AND...
Is “else if” a single keyword?
...s section on keywords.
The grammar in section 6.4 also makes this clear:
selection-statement:
if ( condition ) statement
if ( condition ) statement else statement
The if in else if is a statement following the else term. The section also says:
[...]The substatement in a selection-statement...