Removes IO modules from Daru

Gemfile

@@ -1,2 +1,3 @@
 source 'https://rubygems.org'
 gemspec
+gem 'daru-io', :git => 'https://github.com/athityakumar/daru-io.git'

lib/daru.rb

@@ -86,16 +86,6 @@ def error msg
   create_has_library :gruff
 end
 
-{'spreadsheet' => '~>1.1.1', 'mechanize' => '~>2.7.5'}.each do |name, version|
-  begin
-    gem name, version
-    require name
-  rescue LoadError
-    Daru.error "\nInstall the #{name} gem version #{version} for using"\
-    " #{name} functions."
-  end
-end
-
 autoload :CSV, 'csv'
 require 'matrix'
 require 'forwardable'
@@ -104,6 +94,8 @@ def error msg
 
 require 'daru/version.rb'
 
+require 'daru/io'
+
 require 'open-uri'
 require 'backports/2.1.0/array/to_h'
 

lib/daru/core/group_by.rb

@@ -11,12 +11,14 @@ def each_group
         end
       end
 
-      TUPLE_SORTER = lambda do |a, b|
-        if a && b
-          a.compact <=> b.compact
-        else
-          a ? 1 : -1
-        end
+      TUPLE_SORTER = lambda do |left, right|
+        return -1 unless right
+        return 1 unless left
+
+        left = left.compact
+        right = right.compact
+        return left <=> right || 0 if left.length == right.length
+        left.length <=> right.length
       end
 
       def initialize context, names

lib/daru/dataframe.rb

@@ -3,7 +3,6 @@
 require 'daru/maths/statistics/dataframe.rb'
 require 'daru/plotting/gruff.rb'
 require 'daru/plotting/nyaplot.rb'
-require 'daru/io/io.rb'
 
 module Daru
   class DataFrame # rubocop:disable Metrics/ClassLength
@@ -14,152 +13,6 @@ class DataFrame # rubocop:disable Metrics/ClassLength
     extend Gem::Deprecate
 
     class << self
-      # Load data from a CSV file. Specify an optional block to grab the CSV
-      # object and pre-condition it (for example use the `convert` or
-      # `header_convert` methods).
-      #
-      # == Arguments
-      #
-      # * path - Local path / Remote URL of the file to load specified as a String.
-      #
-      # == Options
-      #
-      # Accepts the same options as the Daru::DataFrame constructor and CSV.open()
-      # and uses those to eventually construct the resulting DataFrame.
-      #
-      # == Verbose Description
-      #
-      # You can specify all the options to the `.from_csv` function that you
-      # do to the Ruby `CSV.read()` function, since this is what is used internally.
-      #
-      # For example, if the columns in your CSV file are separated by something
-      # other that commas, you can use the `:col_sep` option. If you want to
-      # convert numeric values to numbers and not keep them as strings, you can
-      # use the `:converters` option and set it to `:numeric`.
-      #
-      # The `.from_csv` function uses the following defaults for reading CSV files
-      # (that are passed into the `CSV.read()` function):
-      #
-      #   {
-      #     :col_sep           => ',',
-      #     :converters        => :numeric
-      #   }
-      def from_csv path, opts={}, &block
-        Daru::IO.from_csv path, opts, &block
-      end
-
-      # Read data from an Excel file into a DataFrame.
-      #
-      # == Arguments
-      #
-      # * path - Path of the file to be read.
-      #
-      # == Options
-      #
-      # *:worksheet_id - ID of the worksheet that is to be read.
-      def from_excel path, opts={}, &block
-        Daru::IO.from_excel path, opts, &block
-      end
-
-      # Read a database query and returns a Dataset
-      #
-      # @param dbh [DBI::DatabaseHandle, String] A DBI connection OR Path to a SQlite3 database.
-      # @param query [String] The query to be executed
-      #
-      # @return A dataframe containing the data resulting from the query
-      #
-      # USE:
-      #
-      #  dbh = DBI.connect("DBI:Mysql:database:localhost", "user", "password")
-      #  Daru::DataFrame.from_sql(dbh, "SELECT * FROM test")
-      #
-      #  #Alternatively
-      #
-      #  require 'dbi'
-      #  Daru::DataFrame.from_sql("path/to/sqlite.db", "SELECT * FROM test")
-      def from_sql dbh, query
-        Daru::IO.from_sql dbh, query
-      end
-
-      # Read a dataframe from AR::Relation
-      #
-      # @param relation [ActiveRecord::Relation] An AR::Relation object from which data is loaded
-      # @param fields [Array] Field names to be loaded (optional)
-      #
-      # @return A dataframe containing the data loaded from the relation
-      #
-      # USE:
-      #
-      #   # When Post model is defined as:
-      #   class Post < ActiveRecord::Base
-      #     scope :active, -> { where.not(published_at: nil) }
-      #   end
-      #
-      #   # You can load active posts into a dataframe by:
-      #   Daru::DataFrame.from_activerecord(Post.active, :title, :published_at)
-      def from_activerecord relation, *fields
-        Daru::IO.from_activerecord relation, *fields
-      end
-
-      # Read the database from a plaintext file. For this method to work,
-      # the data should be present in a plain text file in columns. See
-      # spec/fixtures/bank2.dat for an example.
-      #
-      # == Arguments
-      #
-      # * path - Path of the file to be read.
-      # * fields - Vector names of the resulting database.
-      #
-      # == Usage
-      #
-      #   df = Daru::DataFrame.from_plaintext 'spec/fixtures/bank2.dat', [:v1,:v2,:v3,:v4,:v5,:v6]
-      def from_plaintext path, fields
-        Daru::IO.from_plaintext path, fields
-      end
-
-      # Read the table data from a remote html file. Please note that this module
-      # works only for static table elements on a HTML page, and won't work in
-      # cases where the data is being loaded into the HTML table by Javascript.
-      #
-      # By default - all <th> tag elements in the first proper row are considered
-      # as the order, and all the <th> tag elements in the first column are
-      # considered as the index.
-      #
-      # == Arguments
-      #
-      # * path [String] - URL of the target HTML file.
-      # * fields [Hash] -
-      #
-      #   +:match+ - A *String* to match and choose a particular table(s) from multiple tables of a HTML page.
-      #
-      #   +:order+ - An *Array* which would act as the user-defined order, to override the parsed *Daru::DataFrame*.
-      #
-      #   +:index+ - An *Array* which would act as the user-defined index, to override the parsed *Daru::DataFrame*.
-      #
-      #   +:name+ - A *String* that manually assigns a name to the scraped *Daru::DataFrame*, for user's preference.
-      #
-      # == Returns
-      # An Array of +Daru::DataFrame+s, with each dataframe corresponding to a
-      # HTML table on that webpage.
-      #
-      # == Usage
-      #   dfs = Daru::DataFrame.from_html("http://www.moneycontrol.com/", match: "Sun Pharma")
-      #   dfs.count
-      #   # => 4
-      #
-      #   dfs.first
-      #   #
-      #   # => <Daru::DataFrame(5x4)>
-      #   #          Company      Price     Change Value (Rs
-      #   #     0 Sun Pharma     502.60     -65.05   2,117.87
-      #   #     1   Reliance    1356.90      19.60     745.10
-      #   #     2 Tech Mahin     379.45     -49.70     650.22
-      #   #     3        ITC     315.85       6.75     621.12
-      #   #     4       HDFC    1598.85      50.95     553.91
-      def from_html path, fields={}
-        Daru::IO.from_html path, fields
-      end
-
       # Create DataFrame by specifying rows as an Array of Arrays or Array of
       # Daru::Vector objects.
       def rows source, opts={}
@@ -704,6 +557,45 @@ def rolling_fillna(direction=:forward)
       dup.rolling_fillna!(direction)
     end
 
+    # Return unique rows by vector specified or all vectors
+    #
+    # @param vtrs [String][Symbol] vector names(s) that should be considered
+    #
+    # @example
+    #
+    #    => #<Daru::DataFrame(6x2)>
+    #         a   b
+    #     0   1   a
+    #     1   2   b
+    #     2   3   c
+    #     3   4   d
+    #     2   3   c
+    #     3   4   f
+    #
+    #    2.3.3 :> df.unique
+    #    => #<Daru::DataFrame(5x2)>
+    #         a   b
+    #     0   1   a
+    #     1   2   b
+    #     2   3   c
+    #     3   4   d
+    #     3   4   f
+    #
+    #    2.3.3 :> df.unique(:a)
+    #    => #<Daru::DataFrame(5x2)>
+    #         a   b
+    #     0   1   a
+    #     1   2   b
+    #     2   3   c
+    #     3   4   d
+    #
+    def uniq(*vtrs)
+      vecs = vtrs.empty? ? vectors.map(&:to_s) : Array(vtrs)
+      grouped = group_by(vecs)
+      indexes = grouped.groups.values.map { |v| v[0] }.sort
+      row[*indexes]
+    end
+
     # Iterate over each index of the DataFrame.
     def each_index &block
       return to_enum(:each_index) unless block_given?
@@ -1952,16 +1844,6 @@ def to_a
       [each_row.map(&:to_h), @index.to_a]
     end
 
-    # Convert to json. If no_index is false then the index will NOT be included
-    # in the JSON thus created.
-    def to_json no_index=true
-      if no_index
-        to_a[0].to_json
-      else
-        to_a.to_json
-      end
-    end
-
     # Converts DataFrame to a hash (explicit) with keys as vector names and values as
     # the corresponding vectors.
     def to_h
@@ -2023,50 +1905,19 @@ def rename new_name
 
     alias_method :name=, :rename
 
-    # Write this DataFrame to a CSV file.
-    #
-    # == Arguements
-    #
-    # * filename - Path of CSV file where the DataFrame is to be saved.
-    #
-    # == Options
-    #
-    # * convert_comma - If set to *true*, will convert any commas in any
-    # of the data to full stops ('.').
-    # All the options accepted by CSV.read() can also be passed into this
-    # function.
-    def write_csv filename, opts={}
-      Daru::IO.dataframe_write_csv self, filename, opts
-    end
-
-    # Write this dataframe to an Excel Spreadsheet
-    #
-    # == Arguments
-    #
-    # * filename - The path of the file where the DataFrame should be written.
-    def write_excel filename, opts={}
-      Daru::IO.dataframe_write_excel self, filename, opts
+    # Use marshalling to save dataframe to a file.
+    def save filename
+      fp = File.open(filename, 'w')
+      Marshal.dump(self, fp)
+      fp.close
     end
 
-    # Insert each case of the Dataset on the selected table
-    #
-    # == Arguments
-    #
-    # * dbh - DBI database connection object.
-    # * query - Query string.
-    #
-    # @example
-    #
-    #  ds = Daru::DataFrame.new({:id=>Daru::Vector.new([1,2,3]), :name=>Daru::Vector.new(["a","b","c"])})
-    #  dbh = DBI.connect("DBI:Mysql:database:localhost", "user", "password")
-    #  ds.write_sql(dbh,"test")
-    def write_sql dbh, table
-      Daru::IO.dataframe_write_sql self, dbh, table
-    end
+    def self.load filename
+      return false unless File.exist? filename
 
-    # Use marshalling to save dataframe to a file.
-    def save filename
-      Daru::IO.save self, filename
+      o = false
+      File.open(filename, 'r') { |fp| o = Marshal.load(fp) }
+      o
     end
 
     def _dump(_depth)