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How to remove single character from a String
For accessing individual characters of a String in Java, we have String.charAt(2) . Is there any inbuilt function to remove an individual character of a String in java?
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SQL MAX of multiple columns?
... The obvious answer, but it doesn't work with NULL values, and attempting to fix that gets very messy.
– Disillusioned
Jan 23 '12 at 12:49
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Elegant way to invert a map in Scala
Learning Scala currently and needed to invert a Map to do some inverted value->key lookups. I was looking for a simple way to do this, but came up with only:
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java.net.ConnectException: Connection refused
I'm trying to implement a TCP connection, everything works fine from the server's side but when I run the client program (from client computer) I get the following error:
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Principal component analysis in Python
I'd like to use principal component analysis (PCA) for dimensionality reduction. Does numpy or scipy already have it, or do I have to roll my own using numpy.linalg.eigh ?
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Create an array with same element repeated multiple times
In Python, where [2] is a list, the following code gives this output:
25 Answers
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How do I install Python OpenCV through Conda?
I'm trying to install OpenCV for Python through Anaconda , but I can't seem to figure this out.
41 Answers
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Installing rmagick on Ubuntu
I'm trying to get RMagick setup on Ubuntu 10.04. Looked here but had no joy. I even compiled and installed ImageMagick from source, but the instructions here still didn't help me when I try to install RMagick using RubyGems. I got this error:
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What is Node.js' Connect, Express and “middleware”?
Despite knowing JavaScript quite well, I'm confused what exactly these three projects in Node.js ecosystem do. Is it something like Rails' Rack? Can someone please explain?
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What are the primary differences between Haskell and F#? [closed]
I've searched on the Internet for comparisons between F# and Haskell but haven't found anything really definitive. What are the primary differences and why would I want to choose one over the other?
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