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Compare two data.frames to find the rows in data.frame 1 that are not present in data.frame 2
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How do I update if exists, insert if not (AKA “upsert” or “merge”) in MySQL?
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191
Use INSERT ... ON DUPLICATE KEY UPDATE. For example:
INSERT INTO `usage`
(`thing_id`, `times_...
Remove all the elements that occur in one list from another
Let's say I have two lists, l1 and l2 . I want to perform l1 - l2 , which returns all elements of l1 not in l2 .
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Ruby Hash to array of values
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answered Mar 5 '12 at 0:48
Ray ToalRay Toal
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Python OpenCV2 (cv2) wrapper to get image size?
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213
cv2 uses numpy for manipulating images, so the proper and best way to get the size of an image ...
How do I return rows with a specific value first?
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196
On SQL Server, Oracle, DB2, and many other database systems, this is what you can use:
ORDER ...
Safe String to BigDecimal conversion
...ead some BigDecimal values from the string. Let's say I have this String: "1,000,000,000.999999999999999" and I want to get a BigDecimal out of it. What is the way to do it?
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Changing the color of the axis, ticks and labels for a plot in matplotlib
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167
As a quick example (using a slightly cleaner method than the potentially duplicate question):
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Declaring and initializing variables within Java switches
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114
Switch statements are odd in terms of scoping, basically. From section 6.3 of the JLS:
The...