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XPath: How to select elements based on their value?
...st thing is when using [], there are only two types of data:
[number] to select a node from node-set
[bool] to filter a node-set from node-set
In this case, the value is evaluated to boolean by function boolean(), and there is a rule:
Filters are always evaluated with respect to a context.
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Select Pandas rows based on list index
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For large datasets, it is memory efficient to read only selected rows via the skiprows parameter.
Example
pred = lambda x: x not in [1, 3]
pd.read_csv("data.csv", skiprows=pred, index_col=0, names=...)
This will now return a DataFrame from a file that skips all rows except 1 and ...
Correct way to add external jars (lib/*.jar) to an IntelliJ IDEA project
...ps for adding external jars in IntelliJ IDEA:
Click File from the toolbar
Select Project Structure option (CTRL + SHIFT + ALT + S on Windows/Linux, ⌘ + ; on Mac OS X)
Select Modules at the left panel
Select Dependencies tab
Select + icon
Select 1 JARs or directories option
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Making a WinForms TextBox behave like your browser's address bar
...etty straightforward and seems to work in all the scenarios (mousing down, selecting text, tabbing focus, etc.)
bool alreadyFocused;
...
textBox1.GotFocus += textBox1_GotFocus;
textBox1.MouseUp += textBox1_MouseUp;
textBox1.Leave += textBox1_Leave;
...
void textBox1_Leave(object sender, EventAr...
Not equal != operator on NULL
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As a manual workaround, you could commonly SELECT * FROM MyTable WHERE coalesce(MyColumn, 'x') <> 'x' to assign a constant if it is NULL value, providing you give an appropriate datatype for the sentinel value x (in this case a string/char). This is TSQL syntax ...
What is the PostgreSQL equivalent for ISNULL()
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SELECT CASE WHEN field IS NULL THEN 'Empty' ELSE field END AS field_alias
Or more idiomatic:
SELECT coalesce(field, 'Empty') AS field_alias
share...
Laravel Eloquent groupBy() AND also return count of each group
...working for me:
$user_info = DB::table('usermetas')
->select('browser', DB::raw('count(*) as total'))
->groupBy('browser')
->get();
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Mac SQLite editor [closed]
... info.plist and setting it to YES
Running the app on a device
Open iTunes
Select the device
Select the "Apps" tab
Scroll down to the "File Sharing" section and select the app
The .sqlite file should appear in the right hand pane - select it and "Save to..."
Once it's saved open it up in your favour...
Delete branches in Bitbucket
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in Bitbucket go to branches in left hand side menu.
Select your branch you want to delete.
Go to action column, click on three dots (...) and select delete.
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improve t...
LINQ Select Distinct with Anonymous Types
...DelegateComparer<T>(equals,null));
}
}
var uniqueItems=students.Select(s=> new {FirstName=s.FirstName, LastName=s.LastName})
.Distinct((a,b) => a.FirstName==b.FirstName, c => c.FirstName.GetHashCode()).ToList();
Sorry for the messed up formatting earlier
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