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ggplot2 legend to bottom and horizontal
How can I move a ggplot2 legend to the bottom of the plot and turn it horizontally?
2 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...
Different ways of adding to Dictionary
What is the difference in Dictionary.add(key, value) and Dictionary[key] = value ?
8 Answers
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What is Prefix.pch file in Xcode?
...d to make compiling faster. Rather than parsing the same header files over and over, these files get parsed once, ahead of time.
Xcode
In Xcode, you add imports of the header files you want in a “prefix header,” and enabling Precompile Prefix Header so they get precompiled. But the idea behind a...
How to use shell commands in Makefile
I'm trying to use the result of ls in other commands (e.g. echo, rsync):
2 Answers
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Convert JS date time to MySQL datetime
...me? Also is there a way to add a specific number of minutes to JS datetime and then pass it to MySQL datetime?
12 Answers
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Linq: GroupBy, Sum and Count
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I don't understand where the first "result with sample data" is coming from, but the problem in the console app is that you're using SelectMany to look at each item in each group.
I think you just want:
List<ResultLine> result = Lin...
Converting an array of objects to ActiveRecord::Relation
... ActiveRecord::Relation since a Relation is just a builder for a SQL query and its methods do not operate on actual data.
However, if what you want is a relation then:
for ActiveRecord 3.x, don’t call all and instead call scoped, which will give back a Relation which represents the same records...
Why does writeObject throw java.io.NotSerializableException and how do I fix it?
I have this exception and I don't understand why it would be thrown or, how I should handle it.
3 Answers
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Scala: What is the difference between Traversable and Iterable traits in Scala collections?
I have looked at this question but still don't understand the difference between Iterable and Traversable traits. Can someone explain ?
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