add support for Tensors from slices (#90)

* feat: tensor from slice + CPU to array perf

* chore: crystal tool format

Author: stakach

spec/extensions/slice_spec.cr

@@ -0,0 +1,31 @@
+# Copyright (c) 2021 Crystal Data Contributors
+#
+# MIT License
+#
+# Permission is hereby granted, free of charge, to any person obtaining
+# a copy of this software and associated documentation files (the
+# "Software"), to deal in the Software without restriction, including
+# without limitation the rights to use, copy, modify, merge, publish,
+# distribute, sublicense, and/or sell copies of the Software, and to
+# permit persons to whom the Software is furnished to do so, subject to
+# the following conditions:
+#
+# The above copyright notice and this permission notice shall be
+# included in all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+describe Slice do
+  it "creates a Tensor from a stdlib slice" do
+    s = Slice.new(5) { |i| (i + 10).to_u8 }
+    t = s.to_tensor
+    t.shape.should eq [5]
+    t.to_a.should eq s.to_a
+  end
+end

spec/linalg/work_spec.cr

@@ -1,29 +1,29 @@
-# Copyright (c) 2022 Crystal Data Contributors
-#
-# MIT License
-#
-# Permission is hereby granted, free of charge, to any person obtaining
-# a copy of this software and associated documentation files (the
-# "Software"), to deal in the Software without restriction, including
-# without limitation the rights to use, copy, modify, merge, publish,
-# distribute, sublicense, and/or sell copies of the Software, and to
-# permit persons to whom the Software is furnished to do so, subject to
-# the following conditions:
-#
-# The above copyright notice and this permission notice shall be
-# included in all copies or substantial portions of the Software.
-#
-# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
-# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
-# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
-# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
-# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
-# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-
-describe Num::WorkPool do
-  it "can allocate complex numbers" do
-    pool = Num::WorkPool.new
-    pool.get_cmplx(10)
-  end
-end
+# Copyright (c) 2022 Crystal Data Contributors
+#
+# MIT License
+#
+# Permission is hereby granted, free of charge, to any person obtaining
+# a copy of this software and associated documentation files (the
+# "Software"), to deal in the Software without restriction, including
+# without limitation the rights to use, copy, modify, merge, publish,
+# distribute, sublicense, and/or sell copies of the Software, and to
+# permit persons to whom the Software is furnished to do so, subject to
+# the following conditions:
+#
+# The above copyright notice and this permission notice shall be
+# included in all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+describe Num::WorkPool do
+  it "can allocate complex numbers" do
+    pool = Num::WorkPool.new
+    pool.get_cmplx(10)
+  end
+end

src/api.cr

@@ -8,6 +8,7 @@ require "complex"
   require "arrow"
 {% end %}
 
+require "./extensions/slice"
 require "./extensions/array"
 require "./extensions/number"
 

src/extensions/slice.cr

@@ -0,0 +1,43 @@
+# Copyright (c) 2020 Crystal Data Contributors
+#
+# MIT License
+#
+# Permission is hereby granted, free of charge, to any person obtaining
+# a copy of this software and associated documentation files (the
+# "Software"), to deal in the Software without restriction, including
+# without limitation the rights to use, copy, modify, merge, publish,
+# distribute, sublicense, and/or sell copies of the Software, and to
+# permit persons to whom the Software is furnished to do so, subject to
+# the following conditions:
+#
+# The above copyright notice and this permission notice shall be
+# included in all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+struct Slice(T)
+  # Converts a standard library slice to a `Tensor`.
+  # The type of Tensor is inferred from the element type, and alternative
+  # shapes can be provided.
+  #
+  # ## Arguments
+  #
+  # * device : `Num::Storage` - The storage backend on which to place the `Tensor`
+  # * shape : `Array(Int32)?` - An optional shape this slice represents
+  #
+  # ## Examples
+  #
+  # ```
+  # s = Slice.new(200) { |i| (i + 10).to_u8 }
+  # typeof(s.to_tensor) # => Tensor(UInt8, CPU(Float32))
+  # ```
+  def to_tensor(device = CPU, shape : Array(Int32)? = nil)
+    Tensor.from_slice self, device: device, shape: shape
+  end
+end

src/tensor/allocation.cr

@@ -67,7 +67,7 @@ class Tensor(T, S)
   # without having to provide a specific generic type to the array.
   # Since the storage instance is S, having the array passed
   # allows Num to infer T
-  private def initialize(@data : S, shape : Array(Int), from_array : Array(T))
+  private def initialize(@data : S, shape : Array(Int), from_array : Array(T) | Slice(T))
     assert_types
     @shape = shape.map &.to_i
     @strides = Num::Internal.shape_to_strides(shape, Num::RowMajor)
@@ -155,6 +155,22 @@ class Tensor(T, S)
     new(storage, shape, from_array: flat)
   end
 
+  # Creates a Tensor from a standard library slice onto a specified device.
+  # The type of Tensor is inferred from the element type, and alternative
+  # shapes can be provided.
+  #
+  # ## Examples
+  #
+  # ```
+  # s = Slice.new(200) { |i| (i + 10).to_u8 }
+  # Tensor.from_array(s, device: OCL) # => [200] Tensor stored on a GPU
+  # ```
+  def self.from_slice(s : Slice, device = CPU, shape : Array(Int32)? = nil)
+    shape = shape || [s.size]
+    storage = device.new(s.to_unsafe, shape, Num::Internal.shape_to_strides(shape))
+    new(storage, shape, from_array: s)
+  end
+
   # Creates a `Tensor` of a provided shape, filled with 0.  The generic type
   # must be specified.
   #

src/tensor/backends/cpu/impl_convert.cr

@@ -36,7 +36,7 @@ module Num
   # a.to_a # => [0, 1, 2, 3]
   # ```
   def to_a(arr : Tensor(U, CPU(U))) forall U
-    a = [] of U
+    a = Array(U).new(arr.size)
     each(arr) do |el|
       a << el
     end