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artiq/artiq/gui/scientific_spinbox.py

85 lines
2.7 KiB
Python

import re
from math import inf, copysign
from PyQt5 import QtCore, QtGui, QtWidgets
_float_acceptable = re.compile(
r"([-+]?\d*(?:\d|\.\d|\d\.)\d*)(?:[eE]([-+]?\d+))?",
)
_float_intermediate = re.compile(
r"[-+]?\d*\.?\d*(?:(?:(?<=\d)|(?<=\d\.))[eE][-+]?\d*)?",
)
_exp_shorten = re.compile(r"e\+?0*")
class ScientificSpinBox(QtWidgets.QDoubleSpinBox):
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self.setGroupSeparatorShown(False)
self.setInputMethodHints(QtCore.Qt.ImhNone)
self.setCorrectionMode(self.CorrectToPreviousValue)
# singleStep: resolution for step, buttons, accelerators
# decimals: absolute rounding granularity
# precision: number of significant digits shown, %g precision
self.setPrecision()
self.setRelativeStep()
self.setRange(-inf, inf)
self.setValue(0)
# self.setKeyboardTracking(False)
def setPrecision(self, d=None):
if d is None:
d = self.decimals() + 3
self._precision = max(1, int(d))
self._fmt = "{{:.{}g}}".format(self._precision)
def precision(self):
return self._precision
def setRelativeStep(self, s=None):
if s is None:
s = 1 + self.singleStep()
self._relative_step = max(1 + 10**-self.decimals(), float(s))
def relativeStep(self):
return self._relative_step
def setGroupSeparatorShown(self, s):
if s:
raise NotImplementedError
def textFromValue(self, v):
t = self._fmt.format(v)
t = re.sub(_exp_shorten, "e", t, 1)
return t
def valueFromText(self, text):
clean = text
if self.prefix():
clean = clean.split(self.prefix(), 1)[-1]
if self.suffix():
clean = clean.rsplit(self.suffix(), 1)[0]
return round(float(clean), self.decimals())
def validate(self, text, pos):
clean = text
if self.prefix():
clean = clean.split(self.prefix(), 1)[-1]
if self.suffix():
clean = clean.rsplit(self.suffix(), 1)[0]
try:
float(clean) # faster than matching
return QtGui.QValidator.Acceptable, text, pos
except ValueError:
if re.fullmatch(_float_intermediate, clean):
return QtGui.QValidator.Intermediate, text, pos
return QtGui.QValidator.Invalid, text, pos
def stepBy(self, s):
if abs(s) < 10: # unaccelerated buttons, keys, wheel/trackpad
super().stepBy(s)
else: # accelerated PageUp/Down or CTRL-wheel
v = self.value()
v *= self._relative_step**(s/copysign(10., v))
self.setValue(v)