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Ubuntu rails install fails on zlib
I've just moved over to Ubuntu 8.10 as my dev box; it's my first serious foray into Linux as a daily-use OS, and I'm having a hard time getting Rails going. I have followed a number of tutorials which all seem to work fine, but when I try and use gem install or gem update on anything, I get an erro...
SQL query return data from multiple tables
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Part 1 - Joins and Unions
This answer covers:
Part 1
Joining two or more tables using an inner join (See the wikipedia entry for additional info)
How to use a union query
Left and Right Outer Joins (this stackOverflow answer ...
How to create the most compact mapping n → isprime(n) up to a limit N?
...at produces a data structure with lowest memory consumption for the range (1, N], where N is a constant.
Just an example of what I am looking for: I could represent every odd number with one bit e.g. for the given range of numbers (1, 10], starts at 3: 1110
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Display numbers with ordinal suffix in PHP
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15 Answers
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How to update gradle in android studio?
I installed Android Studio 0.1.9. Today I got and update to version 0.2 and of course I updated. After the installation I restarted Android Studio but now I get this message:
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How to calculate the angle between a line and the horizontal axis?
...xtend infinitely and don't start at a particular point).
deltaY = P2_y - P1_y
deltaX = P2_x - P1_x
Then calculate the angle (which runs from the positive X axis at P1 to the positive Y axis at P1).
angleInDegrees = arctan(deltaY / deltaX) * 180 / PI
But arctan may not be ideal, because dividin...
Adding git branch on the Bash command prompt
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13 Answers
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Why does ~True result in -2?
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int(True) is 1.
1 is:
00000001
and ~1 is:
11111110
Which is -2 in Two's complement1
1 Flip all the bits, add 1 to the resulting number and interpret the result as a binary representation of the magnitude and add a negative sign (s...
What causes imported Maven project in Eclipse to use Java 1.5 instead of Java 1.6 by default and how
I imported a Maven project and it used Java 1.5 even though I have 1.6 configured as my Eclipse default Preferences->Java->Installed JREs .
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Difference between `set`, `setq`, and `setf` in Common Lisp?
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173
Originally, in Lisp, there were no lexical variables -- only dynamic ones. And
there was no SE...