Added QDoubleSlider

double_slider.py

@@ -0,0 +1,33 @@
+from __future__ import division
+from future.builtins import super
+
+from PyQt5.QtWidgets import QSlider
+
+
+class QDoubleSlider(QSlider):
+
+    def __init__(self, parent, min_value, max_value, step, init_value=None):
+        super().__init__(parent)
+        self.min_value = min_value
+        self.max_value = max_value
+        self.step = step
+        self.init_value = init_value
+        self.nvalues = int((max_value - min_value)/step)
+
+        true_max_value = min_value + step*self.nvalues
+        if true_max_value != max_value:
+            self.max_value = true_max_value
+
+        self.setMinimum(self.float_2_int(min_value))
+        self.setMaximum(self.float_2_int(max_value))
+        if init_value is not None:
+            self.setValue(self.float_2_int(init_value))
+
+    def int_2_float(self, value):
+        return (self.max_value - self.min_value)*value/self.nvalues + \
+               self.min_value
+
+    def float_2_int(self, value):
+        return int(
+            self.nvalues*(value - self.min_value) /
+            (self.max_value - self.min_value))