factor

Author	SHA1	Message	Date
Alexander Iljin	739adb122d	charts.lines: factor some common code into y-at	2017-04-17 13:54:50 -07:00
Alexander Iljin	c9def10dde	charts.lines: add last2	2017-04-17 13:54:50 -07:00
Alexander Iljin	fb2538a946	charts.lines: add calc-y	2017-04-17 13:54:50 -07:00
Alexander Iljin	8510b351cf	charts.lines: add calc-line-slope	2017-04-17 13:54:50 -07:00
Alexander Iljin	4b416f1a5a	charts: move code related to line drawing to charts.lines	2017-04-17 13:54:50 -07:00