Plot¶

class visualife.core.Plot(viewport, min_screen_x, max_screen_x, min_screen_y, max_screen_y, min_data_x=0, max_data_x=1, min_data_y=0, max_data_y=1, axes_definition='BL')¶

Bases: object

Creates a plot object with axes

Parameters:

viewport (core.HtmlViewport or core.SvgViewport) – selected viewport object to draw a plot
min_screen_x (float) – starting x value to draw a plot in screen coordinates
max_screen_x (float) – ending point x value to draw a plot in screen coordinate
min_screen_y (float) – starting point x value to draw a plot in screen coordinate
max_screen_y (float) – ending point x value to draw a plot in screen coordinate
min_data_x (float) – minimum x data value
max_data_x (float) – maximum x data value
min_data_y (float) – minimum y data value
max_data_y (float) – maximum y data value
axes_definition (string) – string containg letters represents axis to create in a plot <B - bottom, U - upper, R - right, L - left> (“BL” set by default)

The example below creates a plot in a SVG viewport:

drawing = SvgViewport("scatterplot.svg", 0, 0, 800, 400)
plot = Plot(drawing,50,750,50,350,0.0,0.5,0.0,0.5, axes_definition="UBLR")

Viewport is 800x400, the plot takes 700x300 of it (from 50 to 750 and from 50 to 350 along X and Y asis, respectively) All four axis will be shown because of “UBLR” argument. Output plot will be stored in scatterplot.svg file (SVG format). If you want to make a plot on a web-page, use core.HtmlViewport:

from random import random
from browser import document
from visualife.core import HtmlViewport
from visualife.core.Plot import Plot

xy_data = [ (random(), random()) for i in range(500)]
drawing = HtmlViewport(document['svg'],600,400)
pl = Plot(drawing,50,550,50,350,0.0,1.0,0.0,1.0, axes_definition="UBLR")
pl.scatter(xy_data)
pl.draw(grid=True)
drawing.close()

Attributes Summary

`axes`	Dictionary of axes in a plot - key is a letter defines axis (U,B,R,L) and Axis object is a value
`axes_svg`	Returns axes
`clip_path_name`	Defines clip_path_name of this plot
`clip_path_tics`	Defines clip_path_name of this plot
`converter`
`data_ids`	Returns data_ids
`extra_labels`	Provides access to the list of extra labels of this plot
`plot_label`	Defines title (label) of this plot
`plot_label_font_size`	Defines the font size used to draw title (label) of this plot
`viewport`	Returns viewport

Methods Summary

`add_extra_label`(label_text, data_x, data_y, …)	Adds a new label that will be drawn in the plot.
`axes_svg_x`()	Returns axes elements as an svg object
`axes_svg_y`()	Returns axes elements as an svg object
`bars`(args, *kwargs)	Creates a bar plot
`boxes`(args, *kwargs)
`bubbles`(args, *kwargs)	Creates a bubble chart
`clear`()
`draw`(**kwargs)	Draws this plot on its viewport
`draw_axes`()	Draws axes as an <svg> element
`draw_grid`()	Draws grid as an <svg> element
`draw_legend`([position])	Calculates legend position and size and draws it
`draw_plot_label`()	Draws a plot label - its title and all extra labels that has been added to this plot
`line`(args, *kwargs)	Creates a line plot
`prepare_data_colors`(kwargs_dict)	Returns list of colors used to draw points
`scale`(scale)	Scales plot :param scale: provides a scale :type scale: `float`
`scatter`(args, *kwargs)	Creates a scatterplot

Attributes Documentation

axes¶

Dictionary of axes in a plot - key is a letter defines axis (U,B,R,L) and Axis object is a value

Getter:	returns a dictionary holding axes objects; dictionary keys are `B`, `U`, `R` and `L` for bottom, top, right and left axis, respectively
Type:	`dictionary(Axis)`

axes_svg¶: Returns axes

clip_path_name¶

Defines clip_path_name of this plot

Getter:	returns the clip path name
Setter:	sets the new clip path name
Type:	`string`

clip_path_tics¶

Defines clip_path_name of this plot

Getter:	returns the clip path name
Setter:	sets the new clip path name
Type:	`string`

converter¶

data_ids¶: Returns data_ids

extra_labels¶

Provides access to the list of extra labels of this plot

Returns:	a list of labels, each label as a tuple `(x, y, "text", dict)`. The `dict` holds kwargs with plotting style

plot_label¶

Defines title (label) of this plot

Getter:	returns the label as text
Setter:	sets the new label text
Type:	`string`

plot_label_font_size¶

Defines the font size used to draw title (label) of this plot

Getter:	returns the label font size
Setter:	sets the new label font size
Type:	`float`

viewport¶: Returns viewport

Methods Documentation

add_extra_label(label_text, data_x, data_y, **kwargs)¶

Adds a new label that will be drawn in the plot.

Besides tics labels, axis labels, etc a plot may also have extra labels, placed in arbitrary locations given in data coordinates. Plot object will convert these X,Y coordinates do screen coordinates using main X and Y axes

Parameters:	label_text – text to be written in this plot data_x – data X coordinate of a label data_y – data y coordinate of a label kwargs – style parameters
Returns:	None

axes_svg_x()¶: Returns axes elements as an svg object

axes_svg_y()¶: Returns axes elements as an svg object

bars(*args, **kwargs)¶

Creates a bar plot

Keyword Arguments (**kwargs)(**kwargs):

colors (list [ string ], list [ float ] or list [ color in HEX format ]) – define fill color for points; the colors are cycled over for all points, so if the list contains a single elements, all points will have the same fill color
stroke (float or color in HEX format ) - stroke color
width (float) - width of each bar (in data units!)
title (string) - title of this data series; if not provided, the word “bars” will be used
converter_type (string) - converter type to calculate axis range - may be “primary”

(bottom and left axis) or “secondary” (upper and rigth axis)

adjust_range - False if you want to keep values from Plot constructor and True (default) if you want to have automatically adjust scale

boxes(*args, **kwargs)¶

bubbles(*args, **kwargs)¶

Creates a bubble chart

Bubble chart displays three dimensions of data. Radius of each bubble is proportional to the square root of Z value of each point

Parameters:

*args – data to be plotted; see DataSet.__init__() documentation

Keyword Arguments (**kwargs)(**kwargs):

markersize (float) – a value used to scale radius of each bubbles
colors (list [ string ], list [ float ] or list [ color in HEX format ]) – define fill color for points; the colors are cycled over for all points, so if the list contains a single elements, all points will have the same fill color
stroke (float or color in HEX format ) - stroke color
stroke_width (float) - stroke width
title (string) - title of this data series; if not provided, the word “bubble chart” will be used
converter_type (string) - converter type to calculate axis range - may be “primary”

(bottom and left axis) or “secondary” (upper and rigth axis

adjust_range - False if you want to keep values from Plot constructor and True (default) if you want to have automatically adjust scale

clear()¶

draw(**kwargs)¶

Draws this plot on its viewport

Its necessary to call this method at the end of plotting; only then this plot will be actually drawn. Also, any adjustments (e.g. extra labels, axis, etc.) added after this call will not be included in this plot.

Keyword Arguments (kwargs)`(kwargs)`:
	axes (`bool`) – draws axes if `True` (as default) grid (`bool`) – draws grid if `True` (default is `False`) plot_label (`bool` ) – draws plot_label if `True` (as default) legend (string``or ``bool) – legend position; default is `False`; if `True` then default location is set (see `PlotLegend.__init__()`)

draw_axes()¶: Draws axes as an <svg> element

draw_grid()¶: Draws grid as an <svg> element

draw_legend(position='RU')¶: Calculates legend position and size and draws it

draw_plot_label()¶: Draws a plot label - its title and all extra labels that has been added to this plot

line(*args, **kwargs)¶

Creates a line plot

Line plot displays data conected with lines.

Keyword Arguments (**kwargs)(**kwargs):

colors (list [ string ], list [ float ] or list [ color in HEX format ]) – define fill color for points; the colors are cycled over for all points, so if the list contains a single elements, all points will have the same fill color
stroke (float or color in HEX format ) - stroke color
width (float) - stroke width
title (string) - title of this data series; if not provided, the word “line” will be used
converter_type (string) - converter type to calculate axis range - may be “primary”

(bottom and left axis) or “secondary” (upper and rigth axis)

adjust_range - False if you want to keep values from Plot constructor and True (default) if you want to have automatically adjust scale

prepare_data_colors(kwargs_dict)¶

Returns list of colors used to draw points

This method makes the following choice:

if kwargs_dict does not contain "colors" key, a single color will be returned to plot all points the returned color will be selected from the current palette assigned to differentiate between data series

if "colors" provides a string that is a valid color palette name (i.e. registered in styles.known_color_scales) the requested pallete is returned

if "colors" provides a int, the number is interpreted as an index of a color in the data series palette; a single color is returned

if "colors" provides a list of values, a color is evaluated separately for every value using a color map If kwargs_dict provides "cmap" key, the requested color map is used for that purpose; otherwise a default "blues" map is used. In addition, when "cmap_reversed" key is set to True, the cmap will be reversed, e.g. "red_blue" color map will become "blue_red"

The colors are defined based on what user requested by kwargs parameters passed to plotting methods as``bubbles()``, scatter() or line()

scale(scale)¶: Scales plot :param scale: provides a scale :type scale: float

scatter(*args, **kwargs)¶

Creates a scatterplot

Keyword Arguments (**kwargs)(**kwargs):

markersize (float) – size of points of this scatterplot
markerstyle (char) – point type; available types are:
- ‘o’ – circle
- ‘c’ – circle (same as ‘o’)
- ‘s’ – square
- ‘t’ – triangle
- ‘r’ – rhomb
colors (list [ string ], list [ float ] or list [ color in HEX format ]) – define fill color for points; the colors are cycled over for all points, so if the list contains a single elements, all points will have the same fill color
stroke (float or color in HEX format ) - stroke color
stroke_width (float) - stroke width
title (string) - title of this data series; if not provided, the word “scatter” will be used
flush (bool) – if True, the plot will be automatically send to HTML viewport have no efefct on SVG viewport; defalit is True
converter_type (string) - converter type to calculate axis range - may be “primary”

(bottom and left axis) or “secondary” (upper and rigth axis)

adjust_range - False if you want to keep values from Plot constructor and True (default) if you want to have automatically adjust scale