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What is the HTML tabindex attribute?
...ments support the tabindex attribute: anchor, area, button, input, object, select, and textarea. But the HTML5 spec, with accessibility in mind, allows all elements to be assigned tabindex.
--
For example
<ul tabindex="-1">
<li tabindex="1"></li>
<li tabindex="2"><...
What is the difference between IQueryable and IEnumerable?
...es, meaning the custom query logic it receives, e.g., a predicate or value selector, is in the form of an expression tree instead of a delegate to a method.
IEnumerable<T> is great for working with sequences that are iterated in-memory, but
IQueryable<T> allows for out-of memory things ...
Xcode 4 - “Archive” is greyed out?
...
You have to select the device in the schemes menu in the top left where you used to select between simulator/device. It won’t let you archive a build for the simulator.
Or you may find that if the iOS device is already selected the ar...
Frequency table for a single variable
... the columns as such
[my_series[c].value_counts() for c in list(my_series.select_dtypes(include=['O']).columns)]
Breakdown:
my_series.select_dtypes(include=['O'])
Selects just the categorical data
list(my_series.select_dtypes(include=['O']).columns)
Turns the columns f...
If table exists drop table then create it, if it does not exist just create it
...up the old table,
obviously.
Wrapping all statements with something like SELECT GET_LOCK('__upgrade', -1); ... DO RELEASE_LOCK('__upgrade'); allows to just invoke all statements sequentially without error checking, but I don't think it's a good idea: complexity increases and locking functions in M...
Github Push Error: RPC failed; result=22, HTTP code = 413
... Information Services (IIS) Manager
Expand the Server field
Expand Sites
Select the site you want to make the modification for.
In the Features section, double click Configuration Editor
Under Section select: system.webServer > serverRuntime
Modify the uploadReadAheadSize section (The value mus...
Is it possible to Pivot data using LINQ?
...t = GetCustData();
var query = myList
.GroupBy(c => c.CustId)
.Select(g => new {
CustId = g.Key,
Jan = g.Where(c => c.OrderDate.Month == 1).Sum(c => c.Qty),
Feb = g.Where(c => c.OrderDate.Month == 2).Sum(c => c.Qty),
March = g.Where(c => ...
How to split last commit into two in Git
...do and unstage all of the changes from the last commit:
git reset HEAD^
Selectively stage the first round of changes:
git add -p
Commit:
git commit
Commit the rest of the changes:
git commit -a
(In either step, if you undid a commit that added a brand new file and want to add this to the...
Dynamically select data frame columns using $ and a character value
...and some variable names stored in a character vector cols . When I try to select a variable from mtcars using a dynamic subset of cols , nether of these work
...
Using Chrome's Element Inspector in Print Preview Mode?
...versions).
Check the Emulate print media checkbox at the Rendering tab and select the Print media type.
Chrome v48+ (Thanks Alex for noticing):
Open the Developer Tools (CTRLSHIFTI or F12)
Click the Toggle device mode button in the left top corner (CTRLSHIFTM).
Make sure the console is shown by c...