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pandas: How do I split text in a column into multiple rows?
I'm working with a large csv file and the next to last column has a string of text that I want to split by a specific delimiter. I was wondering if there is a simple way to do this using pandas or python?
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java.lang.UnsupportedClassVersionError: Bad version number in .class file?
... suggestions on the web indicate that the code was compiled in one version and executed in another version (new on old). However, I only have one version of JRE on my system. If I run the commands:
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Simple Digit Recognition OCR in OpenCV-Python
...v2). It is just for learning purposes. I would like to learn both KNearest and SVM features in OpenCV.
3 Answers
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Counting inversions in an array
... find all inversion pairs such that A[i] > A[j] . I'm using merge sort and copying array A to array B and then comparing the two arrays, but I'm having a difficult time seeing how I can use this to find the number of inversions. Any hints or help would be greatly appreciated.
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Why is [1,2] + [3,4] = “1,23,4” in JavaScript?
...d for arrays.
What happens is that Javascript converts arrays into strings and concatenates those.
Update
Since this question and consequently my answer is getting a lot of attention I felt it would be useful and relevant to have an overview about how the + operator behaves in general also.
So, h...
Automatic Preferred Max Layout Width is not available on iOS versions prior to 8.0
I opened an existing iOS project with Xcode6 beta6, and Xcode lists the following warning for both Storyboard and Xib files:
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Difference between `set`, `setq`, and `setf` in Common Lisp?
What is the difference between "set", "setq", and "setf" in Common Lisp?
6 Answers
6
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Evenly space multiple views within a container view
...te 'spacer views' that you have set to match heights equally. Then add top and bottom constraints to the labels (see the screenshot).
More specifically, I have a top constraint on 'Spacer View 1' to superview with a height constraint of lower priority than 1000 and with Height Equals to all of ...
When should I use a composite index?
..._C )
will benefit a query that uses those fields for joining, filtering, and sometimes selecting. It will also benefit queries that use left-most subsets of columns in that composite. So the above index will also satisfy queries that need
index( column_A, column_B, column_C )
index( column_A, col...
Get the week start date and week end date from week number
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You can find the day of week and do a date add on days to get the start and end dates..
DATEADD(dd, -(DATEPART(dw, WeddingDate)-1), WeddingDate) [WeekStart]
DATEADD(dd, 7-(DATEPART(dw, WeddingDate)), WeddingDate) [WeekEnd]
You probably also want to l...