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Difference between toFixed() and toPrecision()?
I'm new to JavaScript and just discovered toFixed() and toPrecision() to round numbers. However, I can't figure out what the difference between the two is.
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How to use Active Support core extensions
I have Active Support 3.0.3 installed and Rails 3.0.3 with Ruby 1.8.7.
5 Answers
5
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In Python, what is the difference between “.append()” and “+= []”?
...d will add one item to the list, while += will copy all elements of right-hand-side list into the left-hand-side list.
Update: perf analysis
Comparing bytecodes we can assume that append version wastes cycles in LOAD_ATTR + CALL_FUNCTION, and += version -- in BUILD_LIST. Apparently BUILD_LIST outw...
How to change plot background color?
I am making a scatter plot in matplotlib and need to change the background of the actual plot to black. I know how to change the face color of the plot using:
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java get file size efficiently
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Well, I tried to measure it up with the code below:
For runs = 1 and iterations = 1 the URL method is fastest most times followed by channel. I run this with some pause fresh about 10 times. So for one time access, using the URL is the fastest way I can think of:
LENGTH sum: 10626, per It...
Remove a string from the beginning of a string
...str($str, strlen($prefix));
}
Takes: 0.0369 ms (0.000,036,954 seconds)
And with:
$prefix = 'bla_';
$str = 'bla_string_bla_bla_bla';
$str = preg_replace('/^' . preg_quote($prefix, '/') . '/', '', $str);
Takes: 0.1749 ms (0.000,174,999 seconds) the 1st run (compiling), and 0.0510 ms (0.000,051,...
Extracting specific columns in numpy array
...but say I have an MxN matrix. All I want to do is extract specific columns and store them in another numpy array but I get invalid syntax errors.
Here is the code:
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Bash script to calculate time elapsed
...a script in bash to calculate the time elapsed for the execution of my commands, consider:
10 Answers
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What is the difference between Reader and InputStream?
What is the difference between Reader and InputStream?
And when to use what?
If I can use Reader for reading characters why I will use inputstream, I guess to read objects?
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Can I set an opacity only to the background image of a div?
...nnot be done since opacity affects the whole element including its content and there's no way to alter this behavior. You can work around this with the two following methods.
Secondary div
Add another div element to the container to hold the background. This is the most cross-browser friendly meth...