python - Differential equation using dynamicsymbols in Sympy -


in sympy, tried solve differential equation this:

from sympy import * sympy.physics.vector import dynamicsymbols x = dynamicsymbols('x') diffeq = eq(x(t).diff(t), x(t)) dsolve(diffeq, x(t))

but returns

typeerror                           traceback (most recent call last) <ipython-input-10-8a45d7148b24> in <module>()       1 x = dynamicsymbols('x') ----> 2 diffeq = eq(x(t).diff(t), x(t))       3 dsolve(diffeq, x(t))  typeerror: 'x' object not callable

as far understand, dynamicsymbols creates function of t, how use in differential equation?

sympy docs bit confusing output of 

print(x)

is in fact

x(t)

however doesn't mean supposed call x(t):

from sympy import * sympy.physics.vector import dynamicsymbols x = dynamicsymbols('x') diffeq = eq(diff(x, symbol('t')), x) dsolve(diffeq, x)   # eq(x(t), c1*exp(t))

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