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How to solve error “Missing `secret_key_base` for 'production' environment” (Rails 4.1)
I created a Rails application, using Rails 4.1, from scratch and I am facing a strange problem that I am not able to solve.
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How to align absolutely positioned element to center?
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224
If you set both left and right to zero, and left and right margins to auto you can center an abs...
How to sort two lists (which reference each other) in the exact same way
...ly simple using python's built-in zip function:
>>> list1 = [3,2,4,1, 1]
>>> list2 = ['three', 'two', 'four', 'one', 'one2']
>>> list1, list2 = zip(*sorted(zip(list1, list2)))
>>> list1
(1, 1, 2, 3, 4)
>>> list2
('one', 'one2', 'two', 'three', 'four')
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Get the Row(s) which have the max count in groups using groupby
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341
In [1]: df
Out[1]:
Sp Mt Value count
0 MM1 S1 a 3
1 MM1 S1 n 2
2 M...
Counting the number of elements with the values of x in a vector
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You can just use table():
> a <- table(numbers)
> a
numbers
4 5 23 34 43 54 56 65 67 324 435 453 456 567 657
2 1 2 2 1 1 2 1 2 1 3 1 1 1 1
Then you can subset it:
> a[names(a)==435]
435
3
Or convert it into a data.frame if you're mor...
SQL - The conversion of a varchar data type to a datetime data type resulted in an out-of-range valu
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MaheMahe
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Which version of PostgreSQL am I running?
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1674
Run this query from PostgreSQL:
SELECT version();
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How to check the extension of a filename in a bash script?
...of $file equal to .txt?" If so, you can use the following:
if [ ${file: -4} == ".txt" ]
Note that the space between file: and -4 is required, as the ':-' modifier means something different.
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How can I expand and collapse a using javascript?
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184
Okay, so you've got two options here :
Use jQuery UI's accordion - its nice, easy and fast. Se...