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How to set DOM element as the first child?
I have element E and I'm appending some elements to it. All of a sudden, I find out that the next element should be the first child of E. What's the trick, how to do it? Method unshift doesn't work because E is an object, not array.
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Adding a column to an existing table in a Rails migration
...cord::Migration[5.0]
def change
end
end
In that case you have to manually an add_column to change:
class AddEmailToUsers < ActiveRecord::Migration[5.0]
def change
add_column :users, :email, :string
end
end
And then run rake db:migrate
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How to recursively delete an entire directory with PowerShell 2.0?
What is the simplest way to forcefully delete a directory and all its subdirectories in PowerShell? I am using PowerShell V2 in Windows 7.
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Getting All Variables In Scope
Is there a way to get all variables that are currently in scope in javascript?
10 Answers
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How can I get useful error messages in PHP?
...ple syntax error (wrong bracket, missing semicolon), or a failed function call, or something else entirely.
43 Answers
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Delete rows from a pandas DataFrame based on a conditional expression involving len(string) giving K
...df = df.drop(df[<some boolean condition>].index)
Example
To remove all rows where column 'score' is < 50:
df = df.drop(df[df.score < 50].index)
In place version (as pointed out in comments)
df.drop(df[df.score < 50].index, inplace=True)
Multiple conditions
(see Boolean Indexing...
Is there a way to programmatically scroll a scroll view to a specific edit text?
...way to scroll to an EditText object (or any other view object) programmatically?
22 Answers
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Workflow for statistical analysis and report writing
... for data analysis related to custom report writing? The use-case is basically this:
14 Answers
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How to get Last record from Sqlite?
... This is very bad request for that purpose because sqlite should sort all records by their id (slow) before returning the result, Stephen Nguyen gave optimal request with DESC and LIMIT 1
– Artem Zinnatullin
Nov 15 '13 at 8:13
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get client time zone from browser [duplicate]
...fset. Learn more at the MDN reference.
Compatibility table - as of March 2019, works for 90% of the browsers in use globally. Doesn't work on Internet Explorer.
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