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ActiveRecord: size vs count
In Rails, you can find the number of records using both Model.size and Model.count . If you're dealing with more complex queries is there any advantage to using one method over the other? How are they different?
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how to set “camera position” for 3d plots using python/matplotlib?
I'm learning how to use mplot3d to produce nice plots of 3d data and I'm pretty happy so far. What I am trying to do at the moment is a little animation of a rotating surface. For that purpose, I need to set a camera position for the 3D projection. I guess this must be possible since a surface can b...
What does multicore assembly language look like?
Once upon a time, to write x86 assembler, for example, you would have instructions stating "load the EDX register with the value 5", "increment the EDX" register, etc.
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How to normalize an array in NumPy?
I would like to have the norm of one NumPy array. More specifically, I am looking for an equivalent version of this function
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How do I upgrade my ruby 1.9.2-p0 to the latest patch level using rvm?
...rent version of ruby is ruby 1.9.2p0 (2010-08-18 revision 29036) [x86_64-darwin10.5.0] but I want to update it to the latest patch level using rvm. How can I do this?
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~x + ~y == ~(x + y) is always false?
Does this code always evaluate to false? Both variables are two's complement signed ints.
11 Answers
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Fastest way to remove first char in a String
Say we have the following string
4 Answers
4
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How is “=default” different from “{}” for default constructor and destructor?
I originally posted this as a question only about destructors, but now I'm adding consideration of the default constructor. Here's the original question:
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How to open, read, and write from serial port in C?
I am a little bit confused about reading and writing to a serial port. I have a USB device in Linux that uses the FTDI USB serial device converter driver. When I plug it in, it creates: /dev/ttyUSB1.
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Find which version of package is installed with pip
Using pip, is it possible to figure out which version of a package is currently installed?
15 Answers
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