plot error after a "clean" simpify check up about sympy

[bjodah]

I see, one way for lambdify to already raise an exception is to use a printer without allow_unknown_functions set to False. Example:

>>> from sympy.printing.numpy import NumPyPrinter as P
>>> p = P({'inline': True, 'allow_unknown_functions': False})  # 2nd opt defaults to False, but True in lambdify
>>> lambdify(x, parse_expr('nonsense(x)'), printer=p)
PrintMethodNotImplementedError: Unsupported by <class 'sympy.printing.numpy.NumPyPrinter'>: nonsense
Set the printer option 'strict' to False in order to generate partially printed code.

Exactly how to inject this into the sympy.plotting machinery is unfortunately not something I'm familiar with.

[bjodah]

It's a bit hard to give advice here. If there is an underlying issue with sympy at play here, this is the right place to ask, but I don't think you've given us all the relevant code? (from the traceback I see lambdify being used, but I see no call to lambdify in your provided code).

If your question is about how to structure your code (what to put in try/except blocks, in your case perhaps both the parsing of the string, as well as the call doing the numerical evaluation is what you want), then the "Discussions" tab or one of stackexchange's sites is a better place to discuss design of 3rd party libraries/applications?

[Napain]

It's a bit hard to give advice here. If there is an underlying issue with sympy at play here, this is the right place to ask, but I don't think you've given us all the relevant code? (from the traceback I see lambdify being used, but I see no call to lambdify in your provided code).

Here are my import. I don't use the lambdify function in any of my code.

from sympy.plotting import plot 
from sympy import * 

I y try with a condition like this one (Code below for the method "plot_any") It is also import to note that I name my class "check_methods" This is a rookie mistake by me, it should be name "CheckMethods" so we undertand is a class.

class Plot(check_methods):

    def __init__(self):
        pass

    def plot_any (self):
        checking = CheckMethods('Input your equation : ')
        equation = checking.check_sympy_equation()
        function = str(equation)
        if equation != False:
             print( ":---------------------",equation, ":---------------------")
             x_min, x_max = self.linspace()
             x = symbols('x') 
             plot(equation,(x,x_min,x_max), line_color = 'red')

Anyway, this condition allow me to check if the input is passing the Check on the try/except blocks. Again If a pass an input like "2?0~" The try/except block actually return the False and the code works as I intended.

I figured this transformation comes from a "valid" input in the try block like "sinus(x)" (instead of sin(x)).
the input "sinus(x)" is a valid input, but the plot method doesn't recognize the "sinus(x)" and throws an error.

I was thinking of doing another method that checks if the plot is possible. I just want to know what simpify allows input that are not "plotable"

[sylee957]

What is the code for self.linspace?
I think that you are hiding some details about the class, however, please show the details about the class because we cannot investigate the problem further.

however, the error is likely from giving wrong type for x_min, x_max
x_min, x_max should always be Python numbers, or SymPy numbers, and you may likely have some symbolic expressions that has variables like x, which does not have concrete numeric values, and which is invalid for plotting.

[Napain]

What is the code for self.linspace? I think that you are hiding some details about the class, however, please show the details about the class because we cannot investigate the problem further.

however, the error is likely from giving wrong type for x_min, x_max x_min, x_max should always be Python numbers, or SymPy numbers, and you may likely have some symbolic expressions that has variables like x, which does not have concrete numeric values, and which is invalid for plotting.

self.linspace is a method from the class Plot.
and here is the code for the method.

class Plot(CheckMethods): #Need to check the plot any with plot errors

    def __init__(self):
        pass

    def linspace(self):
        first_x = CheckMethods("Please choose the min value of x: ")
        x_min = first_x.check_float()
        second_x = CheckMethods("Please choose the max value of x: ")
        x_max = second_x.check_float()
        return x_min, x_max

Of course, since there also the usage of checking if the inputs are numbers. I also added a method for the CheckMethods class here below

class CheckMethods:

    def __init__(self, the_string):

        self.number = input(the_string)

    def check_float(self):

        while True:
            try:
                self.number = float(self.number)
                return(self.number)
            except ValueError:
                self.number = input('Please input a number')

I don't share the full project because, first is a project for Uni and I want it to keep it private until I summit it. Second It's long and I thought the necessary code was provide. I apologize for taking so long to answer and not providing enough code.

Don't hesitate to ask for more code. Once I finish it I will gladly share the integrity of my project!