You have to declare variabile in the __init__ method (constructor) and then use it in your code

ex:

class projet(object):
    def __init__(self):
        self.valCouche = ''

    def nameCouche(self):
        valLissage = float(ui.valLissage.displayText())     
        return (valLissage)         


    def choixTraitement(self):
        ui.okLissage.clicked.connect(p.goLissage)

    def goLissage(self, valCouche):
        if ui.chkboxLissage.isChecked():
            self.valCouche = self.nameCouche() 
            print(self.valCouche) # result is False
            os.system(r'"C:\Program Files\FME\fme.exe" D:\Stelios\..... --MAX_NUM_POINTS {0}'.format(self.valCouche))


Difficulties with re-using a variable
Noether's theorem is one of those surprisingly clear results of mathematical calculations, for which I am inclined to think that some kind of intuitive understanding should or must be possible. However I don't know of any, do you?

Independence of time &lt;=> energy conservation.
Independence of position &lt;=> momentum conservation.
Independence of direction &lt;=> angular momentum conservation.  

I know that the mathematics leads in the direction of Lie-algebra and such but I would like to discuss whether this theorem can be understood from a non-mathematical point of view also.
