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Throwing the fattest people off of an overloaded airplane.
Let's say you've got an airplane, and it is low on fuel. Unless the plane drops 3000 pounds of passenger weight, it will not be able to reach the next airport. To save the maximum number of lives, we would like to throw the heaviest people off of the plane first.
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How can I have a newline in a string in sh?
... page:
Words of the form $'string' are treated specially. The word expands to
string, with backslash-escaped characters replaced as specified by the
ANSI C standard. Backslash escape sequences, if present, are decoded
as follows:
\a alert (bell)
\b backs...
How can you make a custom keyboard in Android?
I want to make a custom keyboard. I don't know how to do it using XML and Java. The following picture is a model of the keyboard I want to make. It only needs numbers.
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how to prevent “directory already exists error” in a makefile when using mkdir
I need to generate a directory in my makefile and I would like to not get the "directory already exists error" over and over even though I can easily ignore it.
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Input placeholders for Internet Explorer
...s, one I saw was jQuery-html5-placeholder.
I tried the demo out with IE9, and it looks like it wraps your <input> with a span and overlays a label with the placeholder text.
<label>Text:
<span style="position: relative;">
<input id="placeholder1314588474481" name="text" ...
SQL join: selecting the last records in a one-to-many relationship
Suppose I have a table of customers and a table of purchases. Each purchase belongs to one customer. I want to get a list of all customers along with their last purchase in one SELECT statement. What is the best practice? Any advice on building indexes?
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When saving, how can you check if a field has changed?
... if you make changes to the object, save it, then makes additional changes and call save() on it AGAIN, it will still work correctly.
– philfreo
Mar 14 '12 at 22:57
17
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Generate random numbers with a given (numerical) distribution
... You can then use the rvs() method of the distribution object to generate random numbers.
As pointed out by Eugene Pakhomov in the comments, you can also pass a p keyword parameter to numpy.random.choice(), e.g.
numpy.random.choice(numpy.arange(1, 7), p=[0.1, 0.05, 0.05, 0.2, 0.4, 0.2])
If you a...
Understanding the Rails Authenticity Token
... a form to create, update, or destroy a resource, the Rails app creates a random authenticity_token, stores this token in the session, and places it in a hidden field in the form. When the user submits the form, Rails looks for the authenticity_token, compares it to the one stored in the session, an...
How to determine if a string is a number with C++?
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Also doesn't handle negative numbers and non-whole numbers. We can't know what the requirements are based on the question.
– Brennan Vincent
Jan 11 '11 at 6:24
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