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How does one reorder columns in a data frame?
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You can also use the subset function:
data <- subset(data, select=c(3,2,1))
You should better use the [] operator as in the other answers, but it may be useful to know that you can do a subset and a column reorder operation in a single command.
Update:
You can also use the select...
Safe integer parsing in Ruby
I have a string, say '123' , and I want to convert it to the integer 123 .
8 Answers
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Remove the last character in a string in T-SQL?
... ELSE LEFT(@String, LEN(@String) - 1)
END
) END
SELECT @String
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Get all table names of a particular database by SQL query?
...different sql dbms deal with schemas.
Try the following
For SQL Server:
SELECT TABLE_NAME
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_TYPE = 'BASE TABLE' AND TABLE_CATALOG='dbName'
For MySQL:
SELECT TABLE_NAME
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_TYPE = 'BASE TABLE' AND TABLE_SCHEMA='dbN...
Call int() function on every list element?
...int, numbers)
Note: in Python 3.x map returns a map object which you can convert to a list if you want:
numbers = list(map(int, numbers))
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Parse date string and change format
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convert string to datetime object
from datetime import datetime
s = "2016-03-26T09:25:55.000Z"
f = "%Y-%m-%dT%H:%M:%S.%fZ"
out = datetime.strptime(s, f)
print(out)
output:
2016-03-26 09:25:55
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What do I need to do to get Internet Explorer 8 to accept a self signed certificate?
... certificate.”, choose “Continue to this website (not recommended).”
Select Tools➞Internet Options.
Select Security➞Trusted sites➞Sites.
Confirm the URL matches, and click “Add” then “Close”.
Close the “Internet Options” dialog box with either “OK” or “Cancel”.
Refres...
Get a list of checked checkboxes in a div using jQuery
I want to get a list of names of checkboxes that are selected in a div with certain id. How would I do that using jQuery?
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How can I check whether a radio button is selected with JavaScript?
...when one of the fields is null. How can I check whether a radio button is selected?
28 Answers
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Setting JDK in Eclipse
...roperties the "JRE System Library" was still there. When I deleted it and selected "Use default Workspace JRE" only then did it pick up my change. I would have thought Eclipse should have updated my projects JRE when I selected a different JRE for my workspace
– MayoMan
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