Add scale_x_log2(), scale_y_log2() as a shortcut for trans='log2'

future_changes.md

@@ -10,3 +10,4 @@
 - geom_livemap: fix missing styles (e.g. road outline on high zooms) [[#926](https://github.com/JetBrains/lets-plot/issues/926)].
 - geom_livemap: freeze at zoom 10 [[#892](https://github.com/JetBrains/lets-plot/issues/892)].
 - Enormous CPU / Time/ Memory consumption on some data [[#932](https://github.com/JetBrains/lets-plot/issues/932)].
+- scale_x_log2(), scale_y_log2() as a shortcut for trans='log2' [[#922](https://github.com/JetBrains/lets-plot/issues/922)].

python-package/lets_plot/plot/scale_position.py

@@ -13,6 +13,7 @@
  'scale_x_discrete_reversed', 'scale_y_discrete_reversed',
  'scale_x_continuous', 'scale_y_continuous',
  'scale_x_log10', 'scale_y_log10',
+ 'scale_x_log2', 'scale_y_log2',
  'scale_x_reverse', 'scale_y_reverse',
  'scale_x_datetime', 'scale_y_datetime',
  'scale_x_time', 'scale_y_time',
@@ -325,6 +326,150 @@ def scale_y_log10(name=None, *,
  )
 
 
+def scale_x_log2(name=None, *,
+ breaks=None, labels=None,
+ limits=None,
+ expand=None,
+ na_value=None,
+ format=None,
+ position=None
+ ):
+ """
+ Continuous position scale x where trans='log2'.
+
+ Parameters
+ ----------
+ name : str
+ The name of the scale - used as the axis label or the legend title.
+ If None, the default, the name of the scale
+ is taken from the first mapping used for that aesthetic.
+ breaks : list
+ A numeric vector of positions (of ticks).
+ labels : list of str
+ A vector of labels (on ticks).
+ limits : list
+ A numeric vector of length two providing limits of the scale.
+ expand : list
+ A numeric vector of length two giving multiplicative and additive expansion constants.
+ The vector size == 1 => only multiplicative expand (and additive expand by default).
+ Defaults: multiplicative = 0.05, additive = 0.
+ na_value
+ Missing values will be replaced with this value.
+ format : str
+ Define the format for labels on the scale. The syntax resembles Python's:
+ '.2f' -> '12.45'
+ 'Num {}' -> 'Num 12.456789'
+ 'TTL: {.2f}$' -> 'TTL: 12.45$'
+ For more info see https://lets-plot.org/pages/formats.html.
+ position : str
+ The position of the axis:
+
+ - 'left', 'right' or 'both' for y-axis;
+ - 'top', 'bottom' or 'both' for x-axis.
+
+ Returns
+ -------
+ `FeatureSpec`
+ Scale specification.
+
+ Examples
+ --------
+ .. jupyter-execute::
+ :linenos:
+ :emphasize-lines: 6
+
+ import numpy as np
+ from lets_plot import *
+ LetsPlot.setup_html()
+ np.random.seed(42)
+ x = np.power(2, np.random.randint(9, size=100))
+ ggplot({'x': x}, aes(x='x')) + geom_bar() + scale_x_log2()
+
+ """
+ return scale_x_continuous(name,
+ breaks=breaks,
+ labels=labels,
+ limits=limits,
+ expand=expand,
+ na_value=na_value,
+ trans='log2',
+ format=format,
+ position=position,
+ )
+
+
+def scale_y_log2(name=None, *,
+ breaks=None, labels=None,
+ limits=None,
+ expand=None,
+ na_value=None,
+ format=None,
+ position=None
+ ):
+ """
+ Continuous position scales y where trans='log2'.
+
+ Parameters
+ ----------
+ name : str
+ The name of the scale - used as the axis label or the legend title.
+ If None, the default, the name of the scale
+ is taken from the first mapping used for that aesthetic.
+ breaks : list
+ A numeric vector of positions (of ticks).
+ labels : list of str
+ A vector of labels (on ticks).
+ limits : list
+ A numeric vector of length two providing limits of the scale.
+ expand : list
+ A numeric vector of length two giving multiplicative and additive expansion constants.
+ The vector size == 1 => only multiplicative expand (and additive expand by default).
+ Defaults: multiplicative = 0.05, additive = 0.
+ na_value
+ Missing values will be replaced with this value.
+ format : str
+ Define the format for labels on the scale. The syntax resembles Python's:
+ '.2f' -> '12.45'
+ 'Num {}' -> 'Num 12.456789'
+ 'TTL: {.2f}$' -> 'TTL: 12.45$'
+ For more info see https://lets-plot.org/pages/formats.html.
+ position : str
+ The position of the axis:
+
+ - 'left', 'right' or 'both' for y-axis;
+ - 'top', 'bottom' or 'both' for x-axis.
+
+ Returns
+ -------
+ `FeatureSpec`
+ Scale specification.
+
+ Examples
+ --------
+ .. jupyter-execute::
+ :linenos:
+ :emphasize-lines: 6
+
+ import numpy as np
+ from lets_plot import *
+ LetsPlot.setup_html()
+ np.random.seed(42)
+ x = np.random.poisson(size=100)
+ ggplot({'x': x}, aes(x='x')) + geom_histogram() + scale_y_log2()
+
+ """
+ return scale_y_continuous(name,
+ breaks=breaks,
+ labels=labels,
+ limits=limits,
+ expand=expand,
+ na_value=na_value,
+ trans='log2',
+ format=format,
+ position=position,
+ )
+
+
 def scale_x_reverse(name=None, *,
  breaks=None, labels=None,
  limits=None,