Class: NMatrix::IO::PointCloud::MetaReader

Inherits:
Object
  • Object
show all
Defined in:
lib/nmatrix/io/point_cloud.rb

Overview

:nodoc:

Constant Summary collapse

ENTRIES =
[:version,  :fields,           :size,  :type,
:count,  :width,  :height,  :viewpoint,  :points,  :data]
ASSIGNS =
[:version=, :fields=,          :size=, :type=,
:count=, :width=, :height=, :viewpoint=, :points=, :data=]
CONVERT =
[:to_s,     :downcase_to_sym,  :to_i,  :downcase_to_sym,
:to_i,   :to_i,   :to_i,    :to_f,       :to_i,    :downcase_to_sym]
DTYPE_CONVERT =
{:byte => :to_i, :int8 => :to_i, :int16 => :to_i,
:int32 => :to_i, :float32 => :to_f, :float64 => :to_f}
INT_DTYPE_BY_SIZE =

For UINT, just add 1 to the index.

{1 => :int8,    2 => :int16,   4 => :int32,
8 => :int64,  16 => :int64}
FLOAT_DTYPE_BY_SIZE =
{1 => :float32, 2 => :float32, 4 => :float32,
8 => :float64,16 => :float64}

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(filename) ⇒ MetaReader

call-seq:

PointCloudReader::MetaReader.new(filename) -> MetaReader
  • Arguments :

    • filename -> String giving the name of the file to be loaded.

  • Raises :

    • NotImplementedError -> only ASCII supported currently

    • IOError -> premature end of file

Open a file and read the metadata at the top; then read the PCD into an NMatrix.

In addition to the fields in the PCD file, there will be at least one additional attribute, :matrix, storing the data.

Raises:

  • (NotImplementedError)


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# File 'lib/nmatrix/io/point_cloud.rb', line 103

def initialize filename
  f = File.new(filename, "r")

  ENTRIES.each.with_index do |entry,i|
    read_entry(f, entry, ASSIGNS[i], CONVERT[i])
  end

  raise(NotImplementedError, "only ASCII supported currently") \
   unless self.data.first == :ascii

  @matrix = NMatrix.new(self.shape, dtype: self.dtype)

  # Do we want to use to_i or to_f?
  convert = DTYPE_CONVERT[self.dtype]

  i = 0
  while line = f.gets
    @matrix[i,:*] = line.chomp.split.map { |f| f.send(convert) }
    i += 1
  end

  raise(IOError, "premature end of file") if i < self.points[0]

end

Instance Attribute Details

#matrixObject (readonly)

Returns the value of attribute matrix.



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# File 'lib/nmatrix/io/point_cloud.rb', line 129

def matrix
  @matrix
end

Class Method Details

.dtype_by_type_and_size(t, s) ⇒ Object

Given a type and a number of bytes, figure out an appropriate dtype



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# File 'lib/nmatrix/io/point_cloud.rb', line 77

def dtype_by_type_and_size t, s
  if t == :f
    FLOAT_DTYPE_BY_SIZE[s]
  elsif t == :u
    return :byte if s == 1
    INT_DTYPE_BY_SIZE[s*2]
  else
    INT_DTYPE_BY_SIZE[s]
  end
end