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What is the difference between ${var}, “$var”, and “${var}” in the Bash shell?
...planations online about this - I haven't been able to refer to them except for using the symbols, which doesn't yield anything.
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Set Colorbar Range in matplotlib
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Using vmin and vmax forces the range for the colors. Here's an example:
import matplotlib as m
import matplotlib.pyplot as plt
import numpy as np
cdict = {
'red' : ( (0.0, 0.25, .25), (0.02, .59, .59), (1., 1., 1.)),
'green': ( (0.0,...
What are the differences between .so and .dylib on osx?
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The Mach-O object file format used by Mac OS X for executables and libraries distinguishes between shared libraries and dynamically loaded modules. Use otool -hv some_file to see the filetype of some_file.
Mach-O shared libraries have the file typ...
What does “Document-oriented” vs. Key-Value mean when talking about MongoDB vs Cassandra?
... database extends the previous model and values are stored in a structured format (a document, hence the name) that the database can understand. For example, a document could be a blog post and the comments and the tags stored in a denormalized way. Since the data are transparent, the store can do m...
super() fails with error: TypeError “argument 1 must be type, not classobj” when parent does not inh
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TypeError: super() argument 1 must be type, not classobj
Try this to see for yourself:
class OldStyle:
pass
class NewStyle(object):
pass
print type(OldStyle) # prints: <type 'classobj'>
print type(NewStyle) # prints <type 'type'>
Note that in Python 3.x, all classes are ...
postgresql COUNT(DISTINCT …) very slow
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@Ankur May I ask you question? Since COUNT(DISTINCT()) performs sorting, it will be definitely helpful to have an index on the column_name especially with relatively small amount of work_mem (where hashing will produce relatevely large amount of batches). Since that, it's not always...
How to unpack and pack pkg file?
I have a pkg file created by Install Maker for Mac.
I want to replace one file in pkg. But I must do this under Linux system, because this is a part of download process. When user starts to download file server must replace one file in pkg.
I have a solution how unpack pkg and replace a file but I d...
assign multiple variables to the same value in Javascript
... these variables would attach to whatever the global context happens to be for that environment (i.e., in Node.js, it would attach to global which is the global context for that environment).
Now you could first declare all your variables and then assign them to the same value and you could avoid t...
What are Makefile.am and Makefile.in?
...e and is used by automake to generate the Makefile.in file (the .am stands for automake).
The configure script typically seen in source tarballs will use the Makefile.in to generate a Makefile.
The configure script itself is generated from a programmer-defined file named either configure.ac or conf...
Separation of JUnit classes into special test package?
...Topic ) recommended in an answer to my previous question, "Sample project for learning JUnit and proper software engineering" . I love it so far!
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