Pythonの数式処理用パッケージ SymPy

SymPyは数式処理の機能を提供

In [43]: import sympy

In [44]: x,y=sympy.symbols('x y')

In [45]: expr=2*x+y

In [46]: expr
Out[46]: 2*x + y

In [47]: expr.subs([(x,2),(y,3)])
Out[47]: 7

In [49]: expr-y
Out[49]: 2*x

数式展開
In [50]: sympy.expand((x+y)**2)
Out[50]: x**2 + 2*x*y + y**2

微分
In [51]: sympy.diff(x**2+2*x+1,x)
Out[51]: 2*x + 2

積分
In [52]: sympy.integrate(3*x**2+2*x,x)
Out[52]: x**3 + x**2