update readme

![BSD-License](https://img.shields.io/badge/license-BSD-blue.svg?style=flat-square)

`plotfx` is a command line tool for creating charts and other data-driven

visualizations. It is partially based on ideas from the "Grammar of Graphics" and

the ggplot2 R library. One of the main goals for PlotFX is that using it should be

simple and fun.

visualizations. It is partially based on ideas from the "Grammar of Graphics" [0].

One of the main goals for PlotFX is that using it should be simple and fun.

PlotFX is a standalone tool - it is not required to know any specific programming

language to use it. Charts are specified using a lightweight syntax that is very

Input File (`example_chart.plot`):

    plot {

      axis-top: off;

      axis-right: off;

      data: csv('city_temperatures.csv');

      ymin: -10;

      ymax: 32;

      x: $month;

      y: $temperature;

      group: $city;

      series {

        title: "New York";

        point-size: 3.3pt;

        xs: csv(testdata/city_temperatures.csv, month);

        ys: csv(testdata/city_temperatures.csv, new_york);

      layer {

        type: lines;

      }

      series {

        title: "北京市";

        point-size: 3.3pt;

        xs: csv(testdata/city_temperatures.csv, month);

        ys: csv(testdata/city_temperatures.csv, beijing);

      layer {

        type: points;

        point-size: 3pt;

      }

      # ...

    }

PlotFX is the successor of the FnordMetric ChartSQL project by the same authors.

Parts of the new chart specification syntax and semantics were inspired by ideas

from the "Grammar of Graphics" and the ggplot2 project.

from the "Grammar of Graphics" [0] and the ggplot2 project.

[0] Wilkinson, L. (1999). The Grammar of Graphics (Springer)

License

-------