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I have, of course, looked around, at such examples as Using Sympy Equations for Plotting and have looked over the docs, https://docs.sympy.org/latest/modules/plotting.html.

I cannot quite tell if my problem is that the data is away from the origin, yet the plot wants the origin included, or if the problem is because my independent/dependent symbols are not traditional 'x' and 'y'.

Here is my ipynb content for a simple example (though unrelated, I am planning on using units - hence the simple example);

import sympy as sym
from sympy import *
from sympy.plotting import plot as symplot

import matplotlib.pyplot as plt

from scimath.units.length import foot, inch, meter
from scimath.units.mass import kg, gram
from scimath.units.pressure import bar, pascal
from scimath.units.energy import joule, kJ
from scimath.units.power import watt, kilowatt
from scimath.units.volume import m3, cm3
from scimath.units.time import minute, second
from scimath.units.temperature import kelvin
from scimath.units.substance import mol, kmol

init_printing(use_unicode=True)

Cp, T1, T2, V1, V2, DT = sym.symbols('Cp, T1, T2, V1, V2, DT')

eq = Eq(Cp*T2 + (1/2)*V2**2 - Cp*T1 - (1/2)*V1**2 , 0)

eq1 = sym.simplify(  eq.subs(T2,DT+T1)  )

eq2 = sym.solve(eq1,DT)

eq3 = eq2[0].subs(V1,100).subs(V2,200)

symplot(eq3,(Cp,1000,1500),axes=true,xlim=(1000,1500),axis_center=(1000,0),ylim=(-20,0),autoscale=True,xscale='linear',yscale='linear')

My JupyterLab is on Debian, my python3 modules are all installed via pip (locally) and are current - sympy - 1.5.1, jupyter = 1.0.0, jupyterlab - 2.1.4, jupyterlab-server - 1.0.7, python3 - 3.8.3, and I run it in Firefox, etc.

enter image description here

nate
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    Sympy plotting is rather limited at the moment. Did you try installing the latest version (1.6)? In this case you could also consider lambdifying the expression and plot it directly with matplotlib. – JohanC Jun 02 '20 at 11:28
  • I had thought I was updated - sympy 1.6 did work now (or after a restart haha). Nothing against numpy, I just try not to bring in too much stuff, but xx = [1,2,3,4], yy = list( map( lambda x: x**2 , xx) ), plt.plot(xx,yy,'bo') worked as well. Thanks! – nate Jun 02 '20 at 14:28

0 Answers0