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Why is 1/1/1970 the “epoch time”?
...ess than 829 days. For this reason, the time represented by the number 0 (called the epoch) had to be set in the very recent past. As this was in the early 1970s, the epoch was set to 1971-1-1.
Later, the system time was changed to increment every second, which increased the span of time that could...
no acceptable C compiler found in $PATH when installing python
I'm trying to install new python environment on my shared hosting. I follow the steps written in this post :
11 Answers
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Numpy argsort - what is it doing?
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[2, 3, 1, 0] indicates that the smallest element is at index 2, the next smallest at index 3, then index 1, then index 0.
There are a number of ways to get the result you are looking for:
import numpy as np
import scipy.stats as stats
def using_indexed_ass...
Moving decimal places over in a double
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which prints:
12.34
This works because Double.toString(d) performs a small amount of rounding on your behalf, but it is not much. If you are wondering what it might look like without rounding:
System.out.println(new BigDecimal(0.1));
System.out.println(new BigDecimal(x));
prints:
0.100000000...
Calculating Pearson correlation and significance in Python
...trictly speaking, Pearson's correlation requires
that each dataset be normally distributed. Like other correlation
coefficients, this one varies between -1 and +1 with 0 implying no
correlation. Correlations of -1 or +1 imply an exact linear
relationship. Positive correlations imply that as x in...
MySQL Database won't start in XAMPP Manager-osx
...wnloaded XAMPP about a month ago and it was working just fine. Today I installed a voice recognition software and then restarted my computer. Ever since, MySQL won't start in my manager-osx application. It doesn't throw me an in the application log. This is what it says:
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How to merge every two lines into one from the command line?
...utput is ansi colored. Tested on Ubuntu 13.04
– Leo Gallucci
Dec 9 '13 at 22:54
1
@elgalu: Becaus...
How can I check whether a option already exist in select by JQuery
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-1 You're basically doing the loop yourself instead of letting jQuery do it like all the other answers. Although this would work, it's re-inventing the wheel.
– Peter
Apr 4 '13 at 18:33
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How to find out if a Python object is a string?
...r with unicode.
However, you may not need to do explicit type checking at all. "Duck typing" may fit your needs. See http://docs.python.org/glossary.html#term-duck-typing.
See also What’s the canonical way to check for type in python?
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Changing MongoDB data store directory
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The short answer is that the --dbpath parameter in MongoDB will allow you to control what directory MongoDB reads and writes it's data from.
mongod --dbpath /usr/local/mongodb-data
Would start mongodb and put the files in /usr/local/mongodb-data.
Depending on your distribution and...