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python pandas remove duplicate columns
...,False,True].
Pandas allows one to index using boolean values whereby it selects only the True values. Since we want to keep the unduplicated columns, we need the above boolean array to be flipped (ie [True, True, False] = ~[False,False,True])
Finally, df.loc[:,[True,True,False]] selects only the...
How to compare strings ignoring the case
...t; false
>> require 'active_support/all'
=> true
>> str1.mb_chars.downcase.to_s.casecmp(str2.mb_chars.downcase.to_s) == 0
=> true
It works this way in Ruby 2.3.1 and earlier versions.
For smaller memory footprint you can cherry pick string/multibyte:
require 'active_support'
re...
What are best practices for multi-language database design? [closed]
... you might be thinking, that instead of writing simple queries like this:
SELECT price, name, description FROM Products WHERE price < 100
...you would need to start writing queries like that:
SELECT
p.price, pt.name, pt.description
FROM
Products p JOIN ProductTranslations pt
ON (p.id = ...
Why is C so fast, and why aren't other languages as fast or faster? [closed]
...what the machine does can be seen in the rules that govern the widening of char objects for use in expressions: whether the values of char objects widen to signed or unsigned quantities typically depends on which byte operation is more efficient on the target machine.
...
JPG vs. JPEG image formats
...ut it is inaccurate. • The JPEG group were mostly Unix shops, thus the 4-char .jpeg extension, not because of Mac. • It was the DOS 8.3 limit that caused the shortening to .jpg — windows was just a shell on top of DOS. • The commonly accepted .jpg form is because of programs that had to cope...
Escaping HTML strings with jQuery
... This isn't cross browser safe if your string has whitespaces and \n \r \t chars in it
– nivcaner
Dec 4 '10 at 17:31
20
...
ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.al
...al code
mask = ((r["dt"] >= startdate) & (r["dt"] <= enddate))
selected = r[mask]
looks correct. However, if you do want and, then instead of a and b use (a-b).any() or (a-b).all().
share
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...
Multiline strings in VB.NET
...
I used this variant:
Dim query As String = <![CDATA[
SELECT
a.QuestionID
FROM
CR_Answers a
INNER JOIN
CR_Class c ON c.ClassID = a.ClassID
INNER JOIN
CR_Questions q ON q.QuestionID = a.QuestionID
...
CSS: background image on background color
I have panel which I colored blue if this panel is being selected (clicked on it). Additionally, I add a small sign ( .png image) to that panel, which indicates that the selected panel has been already selected before.
...
What's the recommended way to connect to MySQL from Go?
...l", store.user+":"+store.password+"@/"+store.database)
defer con.Close()
Select one row :
row := con.QueryRow("select mdpr, x, y, z from sometable where id=?", id)
cb := new(SomeThing)
err := row.Scan(&cb.Mdpr, &cb.X, &cb.Y, &cb.Z)
Select multiple rows and build an array with re...