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Use of caret symbol( ^ ) in Ruby
So I was playing around with some code and I tried to play around with the power operator. So I thought that perhaps I could use the caret (^) for this purpose, but after using it in:
for i in 0..10 puts "#{i} #{1^i}\n" end I got some really funky results
0 - 1 1 - 0 2 - 3 3 - 2 4 - 5 5 - 4 6 - 7 7 - 6 8 - 9 9 - 8 10 - 11 The only pattern I see is -1 on an odd number and +1 on an even number, but then when I try:
for i in 0..10 puts "#{i} #{2^i}\n" end i get:
0 - 2 1 - 3 2 - 0 3 - 1 4 - 6 5 - 7 6 - 4 7 - 5 8 - 10 9 - 11 10 - 8 wth! So then I kept going up to 4^i and plotted them, the 1^i & 3^i came out with decent patterns but 2^i & 4^i were just all over the place with no visible patterns (though highly unlikely) with just 11 plotting points, so I've come to you ladies and gents asking you:
What on earth is ^ used for?!
1 Answer
In most programming languages, ^ is the XOR operator (Exclusive Or in Wikipedia). XOR is one of the most essential operations in the CPU, it often employed to zero registers (think of a ^= a) because it is fast and has a short opcode.
For the power function, you have to use e.g. ** (e.g. in ruby), java.lang.Math.pow, math.pow, pow etc.
In fact, I couldn't name a programming language that uses ^. It is used in LaTeX for formatting (as superscript, not power function, technically). But the two variants I see all the time are ** (as the power function is directly related to multiplication) and pow(base, exp).
Note that you can compute integer powers of 2 faster using shifts.
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