CrossTable

Cross tabulation (Pivot table) utility to convert table data to a pivot table form.

Source (List table)

os	lang	price
win	ruby	123
linux	ruby	12
mac	php	270
win	java	560
win	php	750
linux	java	950
win	java	1200
win	php	500
mac	php	10
mac	java	566
win	ruby	210

>>>

Destination (Pivot table)

	ruby	java	php
win	333	1760	1250
linux	12	950	0
mac	0	566	280

The test code to get the sample table above.

Installation

Add this line to your application's Gemfile:

gem 'cross_table'

And then execute:

$ bundle

Or install it yourself as:

$ gem install cross_table

Usage

Records Count

require 'cross_table'

cross_tbl = CrossTable.counts_from(
  recs: [],         # Source List Table(Enumerable)
  group_rules: [],  # Grouping Rules (Array of Hash)
  y_keys: [],       # Y-axis Keys (Array)
  x_keys: []        # X-axis Keys (Array)
  ret_type: nil     # Type of returned Pivot table. (nil|:xy_titles|:data_only)
)

Sample test code of CrossTable.counts_from

Sample data and group_rule setting

Fields Summary

require 'cross_table'

cross_tbl = CrossTable.sums_from(
  recs: [],         # Source List Table(Enumerable of Hash)
  field: :fld_name  # Target field name to be summarised
  group_rules: [],  # Grouping Rules (Array of Hash)
  y_keys: [],       # Y-axis Keys (Array)
  x_keys: []        # X-axis Keys (Array)
  ret_type: nil     # Type of returned Pivot table. (nil|:xy_titles|:data_only)
)

Sample test code of CrossTable.sums_from

Sample data and group_rule setting

Fields Average

require 'cross_table'

cross_tbl = CrossTable.avgs_from(
  recs: [],         # Source List Table(Enumerable of Hash)
  field: :fld_name  # Target field name to be summarised
  group_rules: [],  # Grouping Rules (Array of Hash)
  y_keys: [],       # Y-axis Keys (Array)
  x_keys: []        # X-axis Keys (Array)
  ret_type: nil     # Type of returned Pivot table. (nil|:xy_titles|:data_only)
)

Sample test code of CrossTable.avgs_from

Sample data and group_rule setting

Arbitrary property of grouped records

require 'cross_table'

cross_tbl = CrossTable.from(
  recs: [],         # Source List Table(Enumerable of Hash)
  group_rules: [],  # Grouping Rules (Array of Hash)
  y_keys: [],       # Y-axis Keys (Array)
  x_keys: []        # X-axis Keys (Array)
  ret_type: nil     # Type of returned Pivot table. (nil|:xy_titles|:data_only)
  &aggr_proc        # Proc/block to get a value from the arg "group_recs"
)

Sample test code of CrossTable.from to get a Minumum value.

Sample data and group_rule setting

Multiple Keys Grouping

Sample test code of using multilpe keys.

Development

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/masa-kunikata/cross_table.

License

The gem is available as open source under the terms of the MIT License.