1616import numpy as np
1717
1818import matplotlib as mpl
19- from . import cbook
19+ from . import cbook , ticker
2020from .lines import Line2D
2121from .patches import Circle , Rectangle , Ellipse
2222from .transforms import blended_transform_factory
@@ -256,7 +256,8 @@ class Slider(AxesWidget):
256256 val : float
257257 Slider value.
258258 """
259- def __init__ (self , ax , label , valmin , valmax , valinit = 0.5 , valfmt = '%1.2f' ,
259+
260+ def __init__ (self , ax , label , valmin , valmax , valinit = 0.5 , valfmt = None ,
260261 closedmin = True , closedmax = True , slidermin = None ,
261262 slidermax = None , dragging = True , valstep = None ,
262263 orientation = 'horizontal' , ** kwargs ):
@@ -278,8 +279,9 @@ def __init__(self, ax, label, valmin, valmax, valinit=0.5, valfmt='%1.2f',
278279 valinit : float, default: 0.5
279280 The slider initial position.
280281
281- valfmt : str, default: "%1.2f"
282- Used to format the slider value, fprint format string.
282+ valfmt : str, default: None
283+ %-format string used to format the slider value. If None, a
284+ `.ScalarFormatter` is used instead.
283285
284286 closedmin : bool, default: True
285287 Whether the slider interval is closed on the bottom.
@@ -347,13 +349,22 @@ def __init__(self, ax, label, valmin, valmax, valinit=0.5, valfmt='%1.2f',
347349 self .poly = ax .axvspan (valmin , valinit , 0 , 1 , ** kwargs )
348350 self .vline = ax .axvline (valinit , 0 , 1 , color = 'r' , lw = 1 )
349351
350- self .valfmt = valfmt
351- ax .set_yticks ([])
352352 if orientation == 'vertical' :
353353 ax .set_ylim ((valmin , valmax ))
354+ axis = ax .yaxis
354355 else :
355356 ax .set_xlim ((valmin , valmax ))
357+ axis = ax .xaxis
358+
359+ self .valfmt = valfmt
360+ self ._fmt = axis .get_major_formatter ()
361+ if not isinstance (self ._fmt , ticker .ScalarFormatter ):
362+ self ._fmt = ticker .ScalarFormatter ()
363+ self ._fmt .set_axis (axis )
364+ self ._fmt .set_useOffset (False ) # No additive offset.
365+
356366 ax .set_xticks ([])
367+ ax .set_yticks ([])
357368 ax .set_navigate (False )
358369
359370 self .connect_event ('button_press_event' , self ._update )
@@ -365,7 +376,7 @@ def __init__(self, ax, label, valmin, valmax, valinit=0.5, valfmt='%1.2f',
365376 verticalalignment = 'bottom' ,
366377 horizontalalignment = 'center' )
367378
368- self .valtext = ax .text (0.5 , - 0.02 , valfmt % valinit ,
379+ self .valtext = ax .text (0.5 , - 0.02 , self . _format ( valinit ) ,
369380 transform = ax .transAxes ,
370381 verticalalignment = 'top' ,
371382 horizontalalignment = 'center' )
@@ -374,7 +385,7 @@ def __init__(self, ax, label, valmin, valmax, valinit=0.5, valfmt='%1.2f',
374385 verticalalignment = 'center' ,
375386 horizontalalignment = 'right' )
376387
377- self .valtext = ax .text (1.02 , 0.5 , valfmt % valinit ,
388+ self .valtext = ax .text (1.02 , 0.5 , self . _format ( valinit ) ,
378389 transform = ax .transAxes ,
379390 verticalalignment = 'center' ,
380391 horizontalalignment = 'left' )
@@ -435,6 +446,15 @@ def _update(self, event):
435446 if val not in None , self .val ]:
436447 self .set_val (val )
437448
449+ def _format (self , val ):
450+ """Pretty-print *val*."""
451+ if self .valfmt is not None :
452+ return self .valfmt % val
453+ else :
454+ _ , s , _ = self ._fmt .format_ticks ([self .valmin , val , self .valmax ])
455+ # fmt.get_offset is actually the multiplicative factor, if any.
456+ return s + self ._fmt .get_offset ()
457+
438458 def set_val (self , val ):
439459 """
440460 Set slider value to *val*
@@ -451,7 +471,7 @@ def set_val(self, val):
451471 xy [2 ] = val , 1
452472 xy [3 ] = val , 0
453473 self .poly .xy = xy
454- self .valtext .set_text (self .valfmt % val )
474+ self .valtext .set_text (self ._format ( val ) )
455475 if self .drawon :
456476 self .ax .figure .canvas .draw_idle ()
457477 self .val = val
0 commit comments