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Data binding to SelectedItem in a WPF Treeview
How can I retrieve the item that is selected in a WPF-treeview? I want to do this in XAML, because I want to bind it.
20 An...
Pandas selecting by label sometimes return Series, sometimes returns DataFrame
In Pandas, when I select a label that only has one entry in the index I get back a Series, but when I select an entry that has more then one entry I get back a data frame.
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How to generate a random int in C?
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If you need secure random characters or integers:
As addressed in how to safely generate random numbers in various programming languages, you'll want to do one of the following:
Use libsodium's randombytes API
Re-implement what you need from libsod...
Codesign error: Provisioning profile cannot be found after deleting expired profile
...ing profiles. Then reopen the project in xcode, go to the settings and reselect your new profile. This clears up issues like that most of the time. The lines that point to the provisioning profiles will look like this:
PROVISIONING_PROFILE = "487F3EAC-05FB-4A2A-9EA0-31F1F35760EB";
"PROVISIONING_...
HTML for the Pause symbol in audio and video control
...y default) in order to instruct the parser how to transform the bytes into characters correctly. <meta charset="utf-8"/> should be used immediately after <head> in a HTML file, and make sure the correct HTTP headers Content-Type: text/html; charset=utf-8 are set.
Examples:
HTML
&...
Unable to export Apple production push SSL certificate in .p12 format
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Turns out all you have to do is select "My Certificates" on the left panel and it enables the .p12 option.
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Freezing Row 1 and Column A at the same time
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Select cell B2 and click "Freeze Panes" this will freeze Row 1 and Column A.
For future reference, selecting Freeze Panes in Excel will freeze the rows above your selected cell and the columns to the left of your selected ce...
How to avoid warning when introducing NAs by coercion
...t know how to avoid getting a warning when using as.numeric to convert a character vector.
4 Answers
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Random record from MongoDB
...llection.
db.mycoll.aggregate([{ $sample: { size: 1 } }])
If you want to select the random document(s) from a filtered subset of the collection, prepend a $match stage to the pipeline:
// Get one random document matching {a: 10} from the mycoll collection.
db.mycoll.aggregate([
{ $match: { a:...
How to execute a bash command stored as a string with quotes and asterisk [duplicate]
...quotes.
MYSQL='mysql AMORE -u username -ppassword -h localhost -e'
QUERY="SELECT "'*'" FROM amoreconfig" ;# <-- "double"'single'"double"
eval $MYSQL "'$QUERY'"
Bonus: It also reads nice: eval mysql query ;-)
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