Module: Echarts::Speedometer

Defined in:
lib/echarts/speedometer.rb

Class Method Summary collapse

Class Method Details

.compute_angle(value) ⇒ Float

Computes the angle for a given value.

Parameters:

  • value (Float) —

    The value to compute the angle for.

Returns:

  • (Float) —

    The angle in degrees.



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# File 'lib/echarts/speedometer.rb', line 18

def self.compute_angle(value)
  # Compute the angles from the percentages knowing that the startAngle = 225 and the endAngle = -45 clockwise
  225 - (value * 270)
end

.compute_angles(value_in_percentage, min_in_percentage, max_in_percentage) ⇒ Array<Float>

Computes the angles for a given value and the minimum and maximum values in percentage.

Parameters:

  • value_in_percentage (Float) —

    The value in percentage.

  • min_in_percentage (Float) —

    The minimum value in percentage.

  • max_in_percentage (Float) —

    The maximum value in percentage.

Returns:

  • (Array<Float>) —

    The minimum angle, maximum angle, and value angle in degrees.



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# File 'lib/echarts/speedometer.rb', line 29

def self.compute_angles(value_in_percentage, min_in_percentage, max_in_percentage)
  min_angle = compute_angle(min_in_percentage)
  max_angle = compute_angle(max_in_percentage)
  value_angle = compute_angle(value_in_percentage)

  return min_angle, max_angle, value_angle
end

.compute_color(min, max, min_in_percentage, max_in_percentage, color_ok = "limegreen", color_error = "tomato", color_generic = "dodgerblue") ⇒ Array<Array>

Computes the color for the gauge chart based on the minimum and maximum values.

Parameters:

  • min (Numeric) —

    The minimum value.

  • max (Numeric) —

    The maximum value.

  • min_in_percentage (Float) —

    The minimum value in percentage.

  • max_in_percentage (Float) —

    The maximum value in percentage.

  • color_ok (String) (defaults to: "limegreen") —

    The color for values within the range.

  • color_error (String) (defaults to: "tomato") —

    The color for values outside the range.

  • color_generic (String) (defaults to: "dodgerblue") —

    The color for generic values.

Returns:

  • (Array<Array>) —

    An array of color values and their corresponding percentages.



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# File 'lib/echarts/speedometer.rb', line 47

def self.compute_color(min, max, min_in_percentage, max_in_percentage, color_ok = "limegreen", color_error = "tomato", color_generic = "dodgerblue")
  color = []
  color << [min_in_percentage, color_error] if !min.zero? && (max > min || max.zero?)
  color << [max_in_percentage, color_ok] if !max.zero? && (max > min || min.zero?)
  color << [1, max > min ? color_error : ( max == min && max != 0 || max == 0 && min ==0 ? color_generic : color_ok )] 

  color
end

.compute_percentage(value, lower_bound, upper_bound) ⇒ Float

Computes the percentage of a value within a given range.

Parameters:

  • value (Numeric) —

    The value to compute the percentage for.

  • lower_bound (Numeric) —

    The lower bound of the range.

  • upper_bound (Numeric) —

    The upper bound of the range.

Returns:

  • (Float) —

    The percentage of the value within the range.



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# File 'lib/echarts/speedometer.rb', line 10

def self.compute_percentage(value, lower_bound, upper_bound)
  (value - lower_bound) / (upper_bound - lower_bound)
end

.get_config(value, min, max, lower_bound, upper_bound, title, subtitle, vLabel, color_ok = "limegreen", color_error = "tomato", color_generic = "dodgerblue") ⇒ Hash

Computes the options for the gauge chart.

Parameters:

  • value (Numeric) —

    The value to display on the gauge chart.

  • min (Numeric) —

    The minimum value.

  • max (Numeric) —

    The maximum value.

  • lower_bound (Numeric) —

    The lower bound of the range.

  • upper_bound (Numeric) —

    The upper bound of the range.

  • measure_unit (String) —

    The unit of measurement for the value.

  • name (String) —

    The name of the gauge chart.

  • color_ok (String) (defaults to: "limegreen") —

    The color for values within the range.

  • color_error (String) (defaults to: "tomato") —

    The color for values outside the range.

  • color_generic (String) (defaults to: "dodgerblue") —

    The color for generic values.

Returns:

  • (Hash) —

    The options for the gauge chart.



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# File 'lib/echarts/speedometer.rb', line 69

def self.get_config(value, min, max, lower_bound, upper_bound, title, subtitle, vLabel, color_ok = "limegreen", color_error = "tomato", color_generic = "dodgerblue")
  min_in_percentage = compute_percentage(min, lower_bound, upper_bound)
  max_in_percentage = compute_percentage(max, lower_bound, upper_bound)
  value_in_percentage = compute_percentage(value, lower_bound, upper_bound)

  color = compute_color(min, max, min_in_percentage, max_in_percentage, color_ok, color_error, color_generic)
  min_angle, max_angle, value_angle = compute_angles(value_in_percentage, min_in_percentage, max_in_percentage)

  # The gauge chart
  raw_js_options = {
    grid: {
      top: 80,
    },
    title: {
      text: title,
      subtext: subtitle,
    },
    toolbox: {
      top: 'middle',
      right: 5,
      orient: "vertical",
      feature: {
        saveAsImage: {},
      }
    },
    series: [
      {
        type: "gauge",
        min: lower_bound,
        max: upper_bound,
        splitNumber: ((upper_bound - lower_bound) / lower_bound).abs,
        axisLine: {
          lineStyle: {
            width: 30,
            color: color,
          },
        },
        pointer: {
          itemStyle: {
            color: "auto",
          },
        },
        axisTick: {
          distance: -30,
          length: 8,
          lineStyle: {
            color: "#fff",
            width: 2,
          },
        },
        splitLine: {
          distance: -30,
          length: 30,
          lineStyle: {
            color: "#fff",
            width: 4,
          },
        },
        axisLabel: {
          color: "inherit",
          distance: 40,
          fontSize: 20,
        },
        detail: {
          valueAnimation: true,
          # formatter: "#{value.to_i}#{measure_unit}",
          color: "inherit",
        },
        data: [
          {
            value: value,
            name: vLabel,
          },
        ],
      },
      # Dummy Gauge to be used to show the min max thresholds
      {
        type: "gauge",
        z: 3,
        startAngle: min_angle, # Here you can dinamically change the value
        min: min,
        endAngle: max_angle, # Here you can dinamically change the value
        max: max,
        splitNumber: 1,
        axisLabel: {
          distance: -24,
        },
        axisTick: {
          show: false,
        },
        axisLine: {
          lineStyle: {
            width: 0,
          },
        },
        splitLine: {
          distance: -12,
          # length: 50,
          lineStyle: {
            width: 0,
          },
        },
      },
    ],
  }
  
  return raw_js_options
end