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Modifying a subset of rows in a pandas dataframe
...fy this DataFrame (or create a copy) so that B is always NaN whenever A is 0. How would I achieve that?
5 Answers
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Eclipse RCP开发桌面程序 - 更多技术 - 清泛网 - 专注C/C++及内核技术
... Platform的缩写，即富客户平台，是Eclipse进化的产物（自3 0版以后出现），是Eclipse组织向用户提供的强大的开 所谓RCP，就是Rich Client Platform的缩写，即富客户平台，是Eclipse进化的产物（自3.0版以后出现），是Eclipse组织向用户提...
Similarity String Comparison in Java
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answered Jun 5 '09 at 9:59
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How to draw a rounded Rectangle on HTML Canvas?
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50
The HTML5 canvas doesn't provide a method to draw a rectangle with rounded corners.
How about u...
Creating a Pandas DataFrame from a Numpy array: How do I specify the index column and column headers
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350
You need to specify data, index and columns to DataFrame constructor, as in:
>>> pd.Da...
Is object empty? [duplicate]
...n-zero value
// that that property is correct.
if (obj.length > 0) return false;
if (obj.length === 0) return true;
// If it isn't an object at this point
// it is empty, but it can't be anything *but* empty
// Is it empty? Depends on your application.
if (typeof...
How to check if a string is a valid hex color representation?
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/^#[0-9A-F]{6}$/i.test('#AABBCC')
To elaborate:
^ -> match beginning
# -> a hash
[0-9A-F] -> any integer from 0 to 9 and any letter from A to F
{6} -> the previous group appears exactly 6...
How to convert a unix timestamp (seconds since epoch) to Ruby DateTime?
...conds with'%Q tho.
– Mini John
Feb 10 '15 at 2:13
3
To follow up on @TheMiniJohn's answer. It loo...
How do I upgrade my ruby 1.9.2-p0 to the latest patch level using rvm?
My current version of ruby is ruby 1.9.2p0 (2010-08-18 revision 29036) [x86_64-darwin10.5.0] but I want to update it to the latest patch level using rvm. How can I do this?
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How to calculate the angle between a line and the horizontal axis?
... the positive Y axis at P1).
angleInDegrees = arctan(deltaY / deltaX) * 180 / PI
But arctan may not be ideal, because dividing the differences this way will erase the distinction needed to distinguish which quadrant the angle is in (see below). Use the following instead if your language includes ...