## 9.2 Error bars

class `error_bar.T`
  Error bars are used in conjunction with line, scatter, or bar plots to show the confidence interval of each sample value. See Section 7. Class `error_bar.T` is an abstract base class. Actual drawing is done by its subclasses, described next.

class `error_bar.error_bar1`
  This class supports the following attributes:
  `line_style`
    Type: line_style.T ( see Section 14) Default: line_style.black.

  `tic_len`
    Type: length in points ( See Section 4) Default: 10.

    Length of the horizontal bars

class `error_bar.error_bar2`
  This class supports the following attributes:
  `hline_style`
    Type: line_style.T ( see Section 14) Default: line_style.black.

    The style of the horizontal bars.

  `tic_len`
    Type: length in points ( See Section 4) Default: 3.

    The length of the horizontal bars

  `vline_style`
    Type: line_style.T ( see Section 14) Default: None.

    The style of the vertical bar.

class `error_bar.error_bar3`
  This class supports the following attributes:
  `line_style`
    Type: line_style.T ( see Section 14) Default: line_style.black.

class `error_bar.error_bar4`
  This class supports the following attributes:
  `box_width`
    Type: length in points ( See Section 4) Default: 4.

  `fill_style`
    Type: fill_style.T ( see Section 16) Default: fill_style.gray70.

  `line_style`
    Type: line_style.T ( see Section 14) Default: line_style.black.

  `tic_len`
    Type: length in points ( See Section 4) Default: 4.

class `error_bar.error_bar5`
  This class supports the following attributes:
  `line_style`
    Type: line_style.T ( see Section 14) Default: line_style.black.

class `error_bar.error_bar6`
  This class supports the following attributes:
  `box_width`
    Type: length in points ( See Section 4) Default: 4.

  `center_line_style`
    Type: line_style.T ( see Section 14) Default: linestyle: width=0.5, color=default, dash=None, cap=0, join=0.

  `fill_style`
    Type: fill_style.T ( see Section 16) Default: fill_style.gray70.

  `line_style`
    Type: line_style.T ( see Section 14) Default: line_style.black.