Question

这是我第一次接触 sympy。我正在使用带有 pythong 的 DEbian Bullseye。我安装了 git 然后“git clone https://github.com/sympy/sympy.git" 之后：

abraca@SS:~/SymPy$ python3
Python 3.9.2 (default, Feb 28 2021, 17:03:44) 
[GCC 10.2.1 20210110] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> from sympy import *
>>> x = symbols('x')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
NameError: name 'symbols' is not defined
>>> quit()

我做错了什么？

这是我的树的样子，从我的根目录开始：

abraca@SS:~$ ls SymPy/sympy/sympy
abc.py         core         integrals         polys       tensor
algebras       crypto       interactive       printing    testing
assumptions    diffgeom     liealgebras       release.py  this.py
benchmarks     discrete     logic             sandbox     unify
calculus       external     matrices          series       utilities
categories     functions    multipledispatch  sets        vector
codegen        galgebra.py  ntheory           simplify
combinatorics  geometry     parsing           solvers
concrete       holonomic    physics           stats
conftest.py    __init__.py  plotting          strategies

Answer 1

通过 git 安装 sympy 从未奏效。这是有效的（注意所有重要的 3，放在 python 之后，而不是 pip）：

sudo apt install python3-pip
pip3 install sympy

从那时起一切正常：

abraca@SS:~$ python3
Python 3.9.2 (default, Feb 28 2021, 17:03:44) 
[GCC 10.2.1 20210110] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> 
>>> from sympy import *
>>> x=symbols('x')
>>> limit(sin(x)/x,x,0)
1
>>> quit()
abraca@SS:~$

“NameError: name ‘symbols’ is not defined”是什么意思？

1 个答案: