1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
|
require "spec_helper"
require "hamster/vector"
describe Hamster::Vector do
describe "#transpose" do
it "takes a vector of vectors and transposes rows and columns" do
V[V[1, 'a'], V[2, 'b'], V[3, 'c']].transpose.should eql(V[V[1, 2, 3], V["a", "b", "c"]])
V[V[1, 2, 3], V["a", "b", "c"]].transpose.should eql(V[V[1, 'a'], V[2, 'b'], V[3, 'c']])
V[].transpose.should eql(V[])
V[V[]].transpose.should eql(V[])
V[V[], V[]].transpose.should eql(V[])
V[V[0]].transpose.should eql(V[V[0]])
V[V[0], V[1]].transpose.should eql(V[V[0, 1]])
end
it "raises an IndexError if the vectors are not of the same length" do
-> { V[V[1,2], V[:a]].transpose }.should raise_error(IndexError)
end
it "also works on Vectors of Arrays" do
V[[1,2,3], [4,5,6]].transpose.should eql(V[V[1,4], V[2,5], V[3,6]])
end
[10, 31, 32, 33, 1000, 1023, 1024, 1025, 2000].each do |size|
context "on #{size}-item vectors" do
it "behaves like Array#transpose" do
array = rand(10).times.map { size.times.map { rand(10000) }}
vector = V.new(array)
result = vector.transpose
# Array#== uses Object#== to compare corresponding elements,
# so although Vector#== does type coercion, it does not consider
# nested Arrays and corresponding nested Vectors to be equal
# That is why the following ".map { |a| V.new(a) }" is needed
result.should == array.transpose.map { |a| V.new(a) }
result.each { |v| v.class.should be(Hamster::Vector) }
end
end
end
context "on a subclass of Vector" do
it "returns instances of the subclass" do
subclass = Class.new(V)
instance = subclass.new([[1,2,3], [4,5,6]])
instance.transpose.class.should be(subclass)
instance.transpose.each { |v| v.class.should be(subclass) }
end
end
end
end
|
