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php is null or empty?

...LL) {...} Note the ===. When use ==, as you did, PHP treats NULL, false, 0, the empty string, and empty arrays as equal. share | improve this answer | follow ...
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What are the options for storing hierarchical data in a relational database? [closed]

...ttle for one or the other especially if there are more than, say, a lousy 100,000 nodes or so. Using the push stack method can take a whole day to do the conversion on what MLM'ers would consider to be a small million node hierarchy. I thought I'd give Celko a bit of competition by coming up with ...
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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 remove unwanted space between rows and columns in table?

...CSS code: (From here) /* http://meyerweb.com/eric/tools/css/reset/ v2.0 | 20110126 License: none (public domain) */ html, body, div, span, applet, object, iframe, h1, h2, h3, h4, h5, h6, p, blockquote, pre, a, abbr, acronym, address, big, cite, code, del, dfn, em, img, ins, kbd, q, s, samp,...
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surface plots in matplotlib

...t.figure() ax = fig.add_subplot(111, projection='3d') x = y = np.arange(-3.0, 3.0, 0.05) X, Y = np.meshgrid(x, y) zs = np.array(fun(np.ravel(X), np.ravel(Y))) Z = zs.reshape(X.shape) ax.plot_surface(X, Y, Z) ax.set_xlabel('X Label') ax.set_ylabel('Y Label') ax.set_zlabel('Z Label') plt.show() ...
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How to trim a string to N chars in Javascript?

... Why not just use substring... string.substring(0, 7); The first argument (0) is the starting point. The second argument (7) is the ending point (exclusive). More info here. var string = "this is a string"; var length = 7; var trimmedString = string.substring(0, length); ...
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How to get first element in a list of tuples?

... >>> a = [(1, u'abc'), (2, u'def')] >>> [i[0] for i in a] [1, 2] share | improve this answer | follow | ...
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Could not locate Gemfile

... answered Jul 25 '10 at 16:40 JoniJoni 2,85733 gold badges2121 silver badges2222 bronze badges ...
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Rename Pandas DataFrame Index

... but with df.rename() only the column name is renamed. Bug? I'm on version 0.12.0 9 Answers ...
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How to split a long regular expression into multiple lines in JavaScript?

... split into multiple lines in my JavaScript code to keep each line length 80 characters according to JSLint rules. It's just better for reading, I think. Here's pattern sample: ...