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How to get a value from a cell of a dataframe?
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Most answers are using iloc which is good for selection by position.
If you need selection-by-label loc would be more convenient.
For getting a value explicitly (equiv to deprecated
df.get_value('a','A'))
# this is also equivalent to df1.at['a','A']
In [55]: df1....
How can I inspect disappearing element in a browser?
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An alternative method in Chrome:
Open devTools (F12).
Select the "Sources" tab.
While the element you want is displayed, press F8 (or Ctrl+/). This will break script execution and "freeze" the DOM exactly as it is displayed.
From this point, use Ctrl+Shift+C to select the elemen...
Primary key/foreign Key naming convention [closed]
...e the USING syntax in SQL to save some typing and some boilerplate noise:
SELECT name, address, amount
FROM employees JOIN payroll USING (employee_id)
Another argument in favor of convention #2 is that it's the way the relational model was designed.
The significance of each column is
part...
Best way to do Version Control for MS Excel
...to run these macros. In the code viewer, right click on "ThisWorkbook" and select "View Code". You may have to pull down the select box at the top of the code window to change from "(General)" view to "Workbook" view.
Contents of "Workbook" view:
Private Sub Workbook_Open()
ImportCodeModules
End...
Using HTML5/Canvas/JavaScript to take in-browser screenshots
Google's "Report a Bug" or "Feedback Tool" lets you select an area of your browser window to create a screenshot that is submitted with your feedback about a bug.
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Set attribute without value
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Actually, I appear to be adding "value='true'" to my select option, instead of just "value". Ugh.
– RonLugge
Feb 27 '18 at 20:32
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Intellij shortcut to convert code to upper or lower case?
... I have trouble where sometimes pressing CTRL+SHIFT+U just replaces the selected text with the letter U.... sometimes it works, but usually it just does the replacing.
– Trenton
Jul 31 '14 at 16:15
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How to remove Firefox's dotted outline on BUTTONS as well as links?
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Yea it works for me too! Now how can it be done for selects ?
– 7wp
Feb 3 '10 at 19:54
16
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Setting up foreign keys in phpMyAdmin?
..._id, in your case). Then, go to relation view (in the referring table) and select the referred column (so in your case foo.id) and the on update and on delete actions.
I think foreign keys are useful if you have multiple tables linked to one another, in particular, your delete scripts will become v...
Stop the 'Ding' when pressing Enter
...ecutes. The only thing that happens is all the Text in the TextBox becomes selected (and I don't even have code that selects any text)
– bendr
Jun 9 '11 at 10:15
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