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How to sum a variable by group
...umns. First column contains categories such as "First", "Second", "Third", and the second column has numbers that represent the number of times I saw the specific groups from "Category".
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Displaying the build date
... have an app displaying the build number in its title window. That's well and good except it means nothing to most of the users, who want to know if they have the latest build - they tend to refer to it as "last Thursday's" rather than build 1.0.8.4321.
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Remove duplicate rows in MySQL
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The aforementioned bug @DarkMantis referred to and it's solution.
– Jordan Arseno
Jan 23 '13 at 20:47
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Change column type from string to float in Pandas
I want to convert a table, represented as a list of lists, into a Pandas DataFrame . As an extremely simplified example:
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Div width 100% minus fixed amount of pixels
...hout using tables or JavaScript? The white borders represent edges of divs and aren't relevant to the question.
10 Answers
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How can I quantify difference between two images?
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General idea
Option 1: Load both images as arrays (scipy.misc.imread) and calculate an element-wise (pixel-by-pixel) difference. Calculate the norm of the difference.
Option 2: Load both images. Calculate some feature vector for each of them (like a histogram). Calculate distance between featu...
What are the Android SDK build-tools, platform-tools and tools? And which version should be used?
...imentary question, but to my surprise, I could not find any document about Android SDK Build-tools.
Besides Android SDK Tools and Android SDK Platform-tools, there are a bunch of Android SDK Build-tools as shown in the appended screenshot. Could anyone point to a source explaining all of them and he...
Is there a REAL performance difference between INT and VARCHAR primary keys?
...AR as the primary key for reference lists (think US States, Country Codes) and a coworker won't budge on the INT AUTO_INCREMENT as a primary key for all tables.
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Excel: last character/string match in a string
... position of a character/string's last occurrence in a string. Search and find both work left-to-right so I can't think how to apply without lengthy recursive algorithm. And this solution now seems obsolete.
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Column order manipulation using col-lg-push and col-lg-pull in Twitter Bootstrap 3
I'm now reading documentation on Twitter Bootstrap 3, and tried to follow column ordering as shown in this page but hit the wall. I don't understand why such a code works nor how to correctly specify the setting. What I want to show is one grid, which is consisted of length 5, and the other leng...