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What's the best practice to round a float to 2 decimals? [duplicate]

... 160 I was working with statistics in Java 2 years ago and I still got the codes of a function that a...
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Number.sign() in javascript

... More elegant version of fast solution: var sign = number?number<0?-1:1:0 share | improve this answer | follow | ...
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Can I set background image and opacity in the same property?

... Two methods: Convert to PNG and make the original image 0.2 opacity (Better method) have a <div> that is position: absolute; before #main and the same height as #main, then apply the background-image and opacity: 0.2; filter: alpha(opacity=20);. ...
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How to replace NaN values by Zeroes in a column of a Pandas Dataframe?

... 807 I believe DataFrame.fillna() will do this for you. Link to Docs for a dataframe and for a Seri...
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Add column with constant value to pandas dataframe [duplicate]

...numpy.random import randint In [9]: df = DataFrame({'a': randint(3, size=10)}) In [10]: In [10]: df Out[10]: a 0 0 1 2 2 0 3 1 4 0 5 0 6 0 7 0 8 0 9 0 In [11]: s = df.a[:5] In [12]: dfa, sa = df.align(s, axis=0) In [13]: dfa Out[13]: a 0 0 1 2 2 0 3 1 4 0 5 0 6 0 7 0 8 ...
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How can I repeat a character in Bash?

... 410 You can use: printf '=%.0s' {1..100} How this works: Bash expands {1..100} so the command be...
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Moving decimal places over in a double

... 190 If you use double or float, you should use rounding or expect to see some rounding errors. If yo...
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How do you round a floating point number in Perl?

... and floor()? Trig functions? Remember that int() merely truncates toward 0. For rounding to a certain number of digits, sprintf() or printf() is usually the easiest route. printf("%.3f", 3.1415926535); # prints 3.142 The POSIX module (part of the standard Perl distribution) implement...
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How to validate an Email in PHP?

...LTER_VALIDATE_EMAIL) PHP Manual filter_var() Available in PHP >= 5.2.0 If you don't want to change your code that relied on your function, just do: function isValidEmail($email){ return filter_var($email, FILTER_VALIDATE_EMAIL) !== false; } Note: For other uses (where you need Regex)...
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How do you detect Credit card type based on number?

... +50 The credit/debit card number is referred to as a PAN, or Primary Account Number. The first six digits of the PAN are taken from the I...