#
# = Tensor manipulations
# The tensor library is developed by J. Burguet and distributed
# as an add-on package of GSL. See {here}[http://sources.redhat.com/ml/gsl-discuss/2004-q4/msg00053.html"target="_top] and {here}[http://sources.redhat.com/ml/gsl-discuss/2004-q4/msg00055.html"target="_top].
#
# == {}[link:index.html"name="1] Class methods
# ---
# * GSL::Tensor.new(rank, dimention)
# * GSL::Tensor.alloc(rank, dimention)
# * GSL::Tensor[rank, dimention]
#
# Create a tensor of rank rank and dimension dimention.
#
# ---
# * GSL::Tensor.calloc(rank, dimention)
#
# Creates a tensor of rank rank and dimension dimention,
# and initializes all the elements to zero.
#
# ---
# * GSL::Tensor.copy(tensor)
#
# Create a tensor copying the existing tensor tensor.
#
# ---
# * GSL::Tensor.memcpy(dest, src)
#
# Copies the tensor src to another dest. The two
# tensors must have the same shape.
#
# ---
# * GSL::Tensor.swap(a, b)
#
# Exchanges the elements of the tensor a and b.
#
# == {}[link:index.html"name="2] Instance methods
# === {}[link:index.html"name="2.1] Accessing tensor elements
# ---
# * GSL::Tensor#set_zero
#
# Sets all the element of the tensor self to zero.
# ---
# * GSL::Tensor#set_all(x)
#
# Sets all the element of the tensor self to x.
# ---
# * GSL::Tensor#set(indices, x)
# * GSL::Tensor#[indices]=x
#
# Sets the element of the given indices to x.
#
# ---
# * GSL::Tensor#get(indices)
# * GSL::Tensor#[indices]
#
# Returns the tensor element. If the number of indices given is smaller than the
# rank of the tensor, the method GSL::Tensor#subtensor is called.
#
# Ex:
# >> t = Tensor.new(2, 3)
# => #
# >> t.set(1, 2, 2, 123)
# => #
# >> t.get(1, 2, 2)
# => 123.0
# >> t[0, 0, 2] = 456
# => 456
# >> t[0, 0, 2]
# => 456.0
#
# ---
# * GSL::Tensor#subtensor(indices)
# * GSL::Tensor#[indices]
#
# Return a subtensor.
#
# Ex:
# >> require("gsl")
# => true
# >> t = Vector[1..125].to_tensor(3, 5)
# => GSL::Tensor:
# [ 1.000e+00 2.000e+00 3.000e+00 4.000e+00 5.000e+00 6.000e+00 7.000e+00 ... ]
# >> t[0]
# => GSL::Tensor::View:
# [ 1.000e+00 2.000e+00 3.000e+00 4.000e+00 5.000e+00
# 6.000e+00 7.000e+00 8.000e+00 9.000e+00 1.000e+01
# 1.100e+01 1.200e+01 1.300e+01 1.400e+01 1.500e+01
# 1.600e+01 1.700e+01 1.800e+01 1.900e+01 2.000e+01
# 2.100e+01 2.200e+01 2.300e+01 2.400e+01 2.500e+01 ]
# >> t[0,2]
# => GSL::Tensor::View:
# [ 1.100e+01 1.200e+01 1.300e+01 1.400e+01 1.500e+01 ]
# >> t[3,1]
# => GSL::Tensor::View:
# [ 8.100e+01 8.200e+01 8.300e+01 8.400e+01 8.500e+01 ]
# >> t[1][2]
# => GSL::Tensor::View:
# [ 3.600e+01 3.700e+01 3.800e+01 3.900e+01 4.000e+01 ]
#
# ---
# * GSL::Tensor#swap_indices(i, j)
# * GSL::Tensor#data
#
# Returns the data as GSL::Vector::View.
# ---
# * GSL::Tensor#to_v
#
# Creates a new vector from the tensor.
#
# ---
# * GSL::Tensor#to_vector
#
# Converts the tensor of rank 1 into a GSL::Vector::View object.
# ---
# * GSL::Tensor#to_matrix
#
# Converts the tensor of rank 2 into a GSL::Matrix::View object.
#
# === {}[link:index.html"name="2.2] IO
# ---
# * GSL::Tensor#fwrite(io)
# * GSL::Tensor#fwrite(filename)
# * GSL::Tensor#fread(io)
# * GSL::Tensor#fread(filename)
# * GSL::Tensor#fprintf(io, format="%g")
# * GSL::Tensor#fprintf(filename, format="%g")
# * GSL::Tensor#fscanf(io)
# * GSL::Tensor#fscanf(filename)
#
#
# === {}[link:index.html"name="2.3] Max, min
# ---
# * GSL::Tensor#max
# * GSL::Tensor#min
# * GSL::Tensor#minmax
# * GSL::Tensor#max_index
# * GSL::Tensor#min_index
# * GSL::Tensor#minmax_index
#
#
# === {}[link:index.html"name="2.4] Tensor operations
# ---
# * GSL::Tensor#add(b)
# * GSL::Tensor#+(b)
#
# Creates a new tensor adding two tensors self and b.
# ---
# * GSL::Tensor#add!(b)
#
# Adds the element of tensor b to the elements of self , in-place.
# ---
# * GSL::Tensor#sub(b)
# * GSL::Tensor#+(b)
#
# Creates a new tensor subtracting the tensors b from self.
# ---
# * GSL::Tensor#sub!(b)
#
# Subtracts the element of tensor b from the elements of self , in-place.
# ---
# * GSL::Tensor#mul_elements(b)
#
# This calculate element-by-element multiplication of self and b,
# and returns a new tensor.
# ---
# * GSL::Tensor#mul_elements!(b)
#
# Multiplies the elements of tensor self to the elements of b , in-place.
# ---
# * GSL::Tensor#div_elements(b)
# * GSL::Tensor#/(b)
#
# This calculate element-by-element division of self and b,
# and returns a new tensor.
# Multiplies the elements of tensor b to the elements of self , in-place.
# ---
# * GSL::Tensor#div_elements!(b)
#
# Divides the elements of tensor self to the elements of b , in-place.
# ---
# * GSL::Tensor#add_constant(x)
#
# Creates a new tensor adding the constant x to the tensor self.
# ---
# * GSL::Tensor#add_constant!(x)
#
# Adds the constant x to the elements of tensor self , in-place.
# ---
# * GSL::Tensor#scale(x)
#
# Creates a new tensor scaling the tensor self by the constant x.
# ---
# * GSL::Tensor#scale!(x)
#
# Multiplies the constant x to the elements of tensor self , in-place.
# ---
# * GSL::Tensor#add_diagonal(x)
#
# Creates a new tensor adding the constant x to the diagonal elements
# of the tensor self.
# ---
# * GSL::Tensor#add_diagonal!(x)
#
# Adds the constant x to the diagonal elements of tensor self , in-place.
# ---
# * GSL::Tensor#product(b)
# * GSL::Tensor#*(b)
#
# Calculate tensorian product of self and b.
# ---
# * GSL::Tensor#contract(i, j)
#
#
# ---
# * GSL::Tensor#equal?(b, eps = 1e-10)
# * GSL::Tensor#==(b)
#
# Returns true if the tensors have same size and elements
# equal to absolute accurary eps for all the indices,
# and false otherwise.
#
# === {}[link:index.html"name="2.5] Tensor properties
# ---
# * GSL::Tensor#isnull
#
# Returns 1 if all the elements of the tensor are zero, and 0 otherwise.
# ---
# * GSL::Tensor#isnull?
#
# Returns true if all the elements of the tensor are zero, and false otherwise.
#
# ---
# * GSL::Tensor#rank
#
# Returns the rank
# ---
# * GSL::Tensor#dimension
#
# Returns the dimension
# ---
# * GSL::Tensor#size
#
# Returns the size
#
# {prev}[link:rdoc/rngextra_rdoc.html]
# {next}[link:rdoc/narray_rdoc.html]
#
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#
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