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Difference between rake db:migrate db:reset and db:schema:load
...atabases.rake (for Rails 3.2.x) and https://github.com/rails/rails/blob/v4.0.5/activerecord/lib/active_record/railties/databases.rake (for Rails 4.0.x)
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How to Sort Multi-dimensional Array by Value?
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1801
Try a usort, If you are still on PHP 5.2 or earlier, you'll have to define a sorting function f...
What is the difference between hg forget and hg remove?
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edited Jul 11 '09 at 3:37
answered Jul 9 '09 at 4:58
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Is there a way to change the spacing between legend items in ggplot2?
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ggplot2 v3.0.0 released in July 2018 has working options to modify legend.spacing.x, legend.spacing.y and legend.text.
Example: Increase horizontal spacing between legend keys
library(ggplot2)
ggplot(mtcars, aes(factor(cyl), fill ...
Unignore subdirectories of ignored directories in Git
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edited Feb 17 '18 at 14:02
Buo-ren Lin
12077 bronze badges
answered Mar 12 '11 at 21:15
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Split string into an array in Bash
...ace is treated specially.
To access an individual element:
echo "${array[0]}"
To iterate over the elements:
for element in "${array[@]}"
do
echo "$element"
done
To get both the index and the value:
for index in "${!array[@]}"
do
echo "$index ${array[index]}"
done
The last example i...
What are the advantages of NumPy over regular Python lists?
... lists -- a list of lists as you describe, in Python, would take at least 20 MB or so, while a NumPy 3D array with single-precision floats in the cells would fit in 4 MB. Access in reading and writing items is also faster with NumPy.
Maybe you don't care that much for just a million cells, but you ...
How to increment a datetime by one day?
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date = datetime.datetime(2003,8,1,12,4,5)
for i in range(5):
date += datetime.timedelta(days=1)
print(date)
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Different ways of adding to Dictionary
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The performance is almost a 100% identical. You can check this out by opening the class in Reflector.net
This is the This indexer:
public TValue this[TKey key]
{
get
{
int index = this.FindEntry(key);
if (index >= 0)
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Why can't I initialize non-const static member or static array in class?
...reason a is allowed to be initialized while others are not.
Reference:
C++03 9.4.2 Static data members
§4
If a static data member is of const integral or const enumeration type, its declaration in the class definition can specify a constant-initializer which shall be an integral constant expre...