Class: NetCDF::Variable

Inherits:
CDMNode show all
Defined in:
lib/netcdf/variable.rb

Overview

A Variable is a logical container for data. It has a dataType, a set of Dimensions that define its array shape, and optionally a set of Attributes. The data is a multidimensional array of primitive types, Strings, or Structures. Data access is done through the read() methods, which return a memory resident Array. Immutable if setImmutable() was called.

Direct Known Subclasses

TimeVariable, VariableWriter

Instance Attribute Summary collapse

Attributes inherited from CDMNode

#netcdf_elmt

Instance Method Summary collapse

Methods inherited from CDMNode

#get_full_name, #get_short_name, #initialize

Constructor Details

This class inherits a constructor from NetCDF::CDMNode

Instance Attribute Details

#attributes ⇒ Object (readonly)

Returns the value of attribute attributes.



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# File 'lib/netcdf/variable.rb', line 34

def attributes
  @attributes
end

#dimensions ⇒ Object (readonly)

Returns the value of attribute dimensions.



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# File 'lib/netcdf/variable.rb', line 35

def dimensions
  @dimensions
end

#index_iterator ⇒ Object (readonly)

Returns the value of attribute index_iterator.



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# File 'lib/netcdf/variable.rb', line 36

def index_iterator
  @index_iterator
end

Instance Method Details

#cached_data? ⇒ Boolean

Has data been read and cached.

Returns:

  • (Boolean) 


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# File 'lib/netcdf/variable.rb', line 200

def cached_data?
  @netcdf_elmt.hasCachedData()
end

#caching=(boolean) ⇒ Object 



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# File 'lib/netcdf/variable.rb', line 346

def caching=(boolean)
  @netcdf_elmt.setCaching(boolean)
end

#caching? ⇒ Boolean

Will this Variable be cached when read.

Returns:

  • (Boolean) 


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# File 'lib/netcdf/variable.rb', line 216

def caching?
  @netcdf_elmt.isCaching()
end

#coordinate_variable? ⇒ Boolean

Calculate if this is a classic coordinate variable: has same name as its first dimension.

Returns:

  • (Boolean) 


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# File 'lib/netcdf/variable.rb', line 225

def coordinate_variable?
  @netcdf_elmt.isCoordinateVariable()
end

#create_new_cache ⇒ Object

Create a new data cache, use this when you dont want to share the cache.



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# File 'lib/netcdf/variable.rb', line 50

def create_new_cache
  @netcdf_elmt.createNewCache()
end

#extra_info ⇒ Object 



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# File 'lib/netcdf/variable.rb', line 42

def extra_info
  @netcdf_elmt.extraInfo()
end

#find_attribute(name, ignore_case = false) ⇒ Object

Finds an attribute by name



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# File 'lib/netcdf/variable.rb', line 58

def find_attribute(name, ignore_case = false)

  if (ignore_case)
    @netcdf_elmt.findAttributeIgnoreCase(name)
  else
    @netcdf_elmt.findAttribute(name)
  end

end

#find_attributes ⇒ Object

Returns the set of attributes for this variable.



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# File 'lib/netcdf/variable.rb', line 80

def find_attributes

  attributes = @netcdf_elmt.getAttributes()
  atts = Array.new
  attributes.each do |att|
    atts << NetCDF::Attribute.new(att)
  end
  atts

end

#find_dimension_index(name) ⇒ Object

Find the index of the named Dimension in this Variable.



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# File 'lib/netcdf/variable.rb', line 72

def find_dimension_index(name)
  @netcdf_elmt.findDimensionIndex(name)
end

#find_dimensions ⇒ Object

Get the list of dimensions used by this variable.



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# File 'lib/netcdf/variable.rb', line 119

def find_dimensions

  dimensions = @netcdf_elmt.getDimensions()
  dims = Array.new
  dimensions.each do |dim|
    dims << NetCDF::Dimension.new(dim)
  end
  dims

end

#get_data_type ⇒ Object

Gets the variable data_type



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# File 'lib/netcdf/variable.rb', line 95

def get_data_type
  @netcdf_elmt.getDataType().toString()
end

#get_description ⇒ Object

Get the description of the Variable.



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# File 'lib/netcdf/variable.rb', line 103

def get_description
  @netcdf_elmt.getDescription()
end

#get_dimension(index) ⇒ Object

Get the ith dimension.



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# File 'lib/netcdf/variable.rb', line 111

def get_dimension(index)
  @netcdf_elmt.getDimension(index)
end

#get_dimensions_string ⇒ Object

Get the list of Dimension names, space delineated.



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# File 'lib/netcdf/variable.rb', line 134

def get_dimensions_string
  @netcdf_elmt.getDimensionsString()
end

#get_element_size ⇒ Object

Get the number of bytes for one element of this Variable.



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# File 'lib/netcdf/variable.rb', line 142

def get_element_size
  @netcdf_elmt.getElementSize()
end

#get_name_and_dimensions ⇒ Object

Get the display name plus the dimensions, eg ‘float name(dim1, dim2)’



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# File 'lib/netcdf/variable.rb', line 150

def get_name_and_dimensions
  @netcdf_elmt.getNameAndDimensions()
end

#get_rank ⇒ Object Also known as: rank

Get the number of dimensions of the Variable.



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# File 'lib/netcdf/variable.rb', line 158

def get_rank
  @netcdf_elmt.getRank()
end

#get_shape(index = nil) ⇒ Object Also known as: shape

Get the shape: length of Variable in each dimension.



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# File 'lib/netcdf/variable.rb', line 168

def get_shape(index = nil)
  if (index)
    @netcdf_elmt.getShape(index)
  else
    @netcdf_elmt.getShape().to_a
  end
end

#get_size ⇒ Object Also known as: size

Get the total number of elements in the Variable.



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# File 'lib/netcdf/variable.rb', line 182

def get_size
  @netcdf_elmt.getSize()
end

#get_units_string ⇒ Object

Get the Unit String for the Variable.



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# File 'lib/netcdf/variable.rb', line 192

def get_units_string
  @netcdf_elmt.getUnitsString()
end

#immutable? ⇒ Boolean

Is this Variable immutable

Returns:

  • (Boolean) 


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# File 'lib/netcdf/variable.rb', line 233

def immutable?
  @netcdf_elmt.isImmutable()
end

#invalidate_cache ⇒ Object

Invalidate the data cache



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# File 'lib/netcdf/variable.rb', line 208

def invalidate_cache
  @netcdf_elmt.invalidateCache()
end

#metadata? ⇒ Boolean

Is this variable metadata?.

Returns:

  • (Boolean) 


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# File 'lib/netcdf/variable.rb', line 241

def metadata?
  @netcdf_elmt.isMetadata()
end

#print ⇒ Object

Prints the content of the current data slice



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# File 'lib/netcdf/variable.rb', line 399

def print
  p to_string
end

#read(*args) ⇒ Object

Reads data for this Variable and sets the variable @data to the memory resident array. :origin int array with the origin of data to be read :shape int array with the shape of the data to be read. If origin or 



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# File 'lib/netcdf/variable.rb', line 285

def read(*args)

  opts = Map.options(args)
  spec = opts.getopt(:spec)
  origin = opts.getopt(:origin)
  shape = opts.getopt(:shape)

  if (origin || shape)
    MDArray.build_from_nc_array(nil, @netcdf_elmt.read(origin.to_java(:int), 
                                                       shape.to_java(:int)))
  elsif (spec)
    MDArray.build_from_nc_array(nil, @netcdf_elmt.read(spec))
  else
    MDArray.build_from_nc_array(nil, @netcdf_elmt.read())
  end
  
end

#read_scalar(type = nil) ⇒ Object 



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# File 'lib/netcdf/variable.rb', line 307

def read_scalar(type = nil)

  if (!type)
    type = get_data_type
  end

  case type
  when "double"
    @netcdf_elmt.readScalarDouble()
  when "float"
    @netcdf_elmt.readScalarFloat()
  when "long"
    @netcdf_elmt.readScalarLong()
  when "int"
    @netcdf_elmt.readScalarInt()
  when "short"
    @netcdf_elmt.readScalarShort()
  when "byte"
    @netcdf_elmt.readScalarByte()
  when "string"
    @netcdf_elmt.readScalarString()
  else
    raise "Unknown type: #{type}"
  end

end

#scalar? ⇒ Boolean

Whether this is a scalar Variable (rank == 0).

Returns:

  • (Boolean) 


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# File 'lib/netcdf/variable.rb', line 249

def scalar?
  @netcdf_elmt.isScalar()
end

#section(*args) ⇒ Object

Create a new Variable that is a logical subsection of this Variable. The subsection can be specified passing the following arguments: shape origin size stride range section spec



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# File 'lib/netcdf/variable.rb', line 362

def section(*args)

  sec = MDArray::Section.build(*args)
  NetCDF::Variable.new(@netcdf_elmt.section(sec.netcdf_elmt))
  
end

#set_cached_data(array, metadata) ⇒ Object 



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# File 'lib/netcdf/variable.rb', line 338

def set_cached_data(array, metadata = nil)
  @netcdf_elmt.setCachedData(array.nc_array, metadata)
end

#to_string ⇒ Object Also known as: to_s

Prints the content of the current data slice



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# File 'lib/netcdf/variable.rb', line 381

def to_string
  @netcdf_elmt.toString()
end

#to_string_debug ⇒ Object 



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# File 'lib/netcdf/variable.rb', line 391

def to_string_debug
  @netcdf_elmt.toSringDebug()
end

#unlimited? ⇒ Boolean

Can this variable’s size grow?.

Returns:

  • (Boolean) 


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# File 'lib/netcdf/variable.rb', line 257

def unlimited?
  @netcdf_elmt.isUnlimited()
end

#unsigned? ⇒ Boolean

Is this Variable unsigned?.

Returns:

  • (Boolean) 


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# File 'lib/netcdf/variable.rb', line 265

def unsigned?
  @netcdf_elmt.isUnsigned()
end

#variable_length? ⇒ Boolean

Does this variable have a variable length dimension? If so, it has as one of its mensions Dimension.VLEN.

Returns:

  • (Boolean) 


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# File 'lib/netcdf/variable.rb', line 274

def variable_length?
  @netcdf_elmt.isVariableLength()
end