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Issue with virtualenv - cannot activate
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source is a shell command designed for users running on Linux (or any Posix, but whatever, not Windows).
On Windows, virtualenv creates a batch file, so you should run venv\Scripts\activate instead (per the virtualenv documentation on the activat...
XmlWriter to Write to a String Instead of to a File
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You need to create a StringWriter, and pass that to the XmlWriter.
The string overload of the XmlWriter.Create is for a filename.
E.g.
using (var sw = new StringWriter()) {
using (var xw = XmlWriter.Create(sw)) {
// Build Xml with xw.
}
return s...
Android Lint contentDescription warning
... Missing contentDescription attribute on image" for imageview. while using android lint
11 Answers
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How to rethrow InnerException without losing stack trace in C#?
...s now the ExceptionDispatchInfo class.
This lets you capture an exception and re-throw it without changing the stack-trace:
try
{
task.Wait();
}
catch(AggregateException ex)
{
ExceptionDispatchInfo.Capture(ex.InnerException).Throw();
}
This works on any exception, not just AggregateExcep...
How to include “zero” / “0” results in COUNT aggregate?
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You want an outer join for this (and you need to use person as the "driving" table)
SELECT person.person_id, COUNT(appointment.person_id) AS "number_of_appointments"
FROM person
LEFT JOIN appointment ON person.person_id = appointment.person_id
GROUP BY p...
Sample random rows in dataframe
...propriate function that would return a specified number of rows picked up randomly without replacement from a data frame in R language? Can anyone help me out?
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How do I scroll to an element within an overflowed Div?
... that can only show 5 at a time. What is a good way to scroll to item #10, and then item #20? I know the height of all the items.
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Is an index needed for a primary key in SQLite?
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It does it for you.
INTEGER PRIMARY KEY columns aside, both UNIQUE and PRIMARY KEY
constraints are implemented by creating an index in the database (in
the same way as a "CREATE UNIQUE INDEX" statement would). Such an
index is used like any other index in the database to optimize
que...
Rails select helper - Default selected value, how?
...g to edit your record.
You need to set the default to your existing value and then only set it to the actual default if you don't have a value. Like so:
f.select :field, options_for_select(value_array, f.object.field || default_value)
For anyone not familiar with f.object.field you always use f....
“Add as Link” for folders in Visual Studio projects
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+1. You could also use <Content ...>, and add <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory> to make Visual Studio copy the resources on build.
– Markus Jarderot
May 18 '12 at 18:12
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