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How to evaluate an integral?
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Hello,
I would like to evaluate the following function which includes an integral. The aim is to get sth. like that: Var_beta_hat_direct = a kind of number. But I only get a symbolic expression and not a number.
Does anybody have an idea?
syms t
Var_beta_hat_direct=vpa(10681743549394799937933824491520*exp(int((140737488355328*exp(-8187485477687969/(4398046511104*(20*heaviside(t - 2000) + 40*heaviside(t - 3000) - 390*heaviside(t - 14000) + 330*heaviside(t)))))/8301382342175545, t, 0, 1671787363946201/274877906944)^(4831891999187463/1125899906842624))*exp(8187485477687969/1715238139330560)*((140737488355328*exp(-int((140737488355328*exp(-8187485477687969/(4398046511104*(20*heaviside(t - 2000) + 40*heaviside(t - 3000) - 390*heaviside(t - 14000) + 330*heaviside(t)))))/8301382342175545, t, 0, 1671787363946201/274877906944)^(4831891999187463/1125899906842624))*exp(-8187485477687969/1715238139330560)*int((140737488355328*exp(-8187485477687969/(4398046511104*(20*heaviside(t - 2000) + 40*heaviside(t - 3000) - 390*heaviside(t - 14000) + 330*heaviside(t)))))/8301382342175545, t, 0, 1671787363946201/274877906944)^(3705992092344839/1125899906842624))/8301382342175545 + (690270285598209*log(int((140737488355328*exp(-8187485477687969/(4398046511104*(20*heaviside(t - 2000) + 40*heaviside(t - 3000) - 390*heaviside(t - 14000) + 330*heaviside(t)))))/8301382342175545, t, 0, 1671787363946201/274877906944))*exp(-int((140737488355328*exp(-8187485477687969/(4398046511104*(20*heaviside(t - 2000) + 40*heaviside(t - 3000) - 390*heaviside(t - 14000) + 330*heaviside(t)))))/8301382342175545, t, 0, 1671787363946201/274877906944)^(4831891999187463/1125899906842624))*exp(-8187485477687969/1715238139330560)*int((140737488355328*exp(-8187485477687969/(4398046511104*(20*heaviside(t - 2000) + 40*heaviside(t - 3000) - 390*heaviside(t - 14000) + 330*heaviside(t)))))/8301382342175545, t, 0, 1671787363946201/274877906944)^(3705992092344839/1125899906842624))/9487294105343480 - (690270285598209*log(int((140737488355328*exp(-8187485477687969/(4398046511104*(20*heaviside(t - 2000) + 40*heaviside(t - 3000) - 390*heaviside(t - 14000) + 330*heaviside(t)))))/8301382342175545, t, 0, 1671787363946201/274877906944))*exp(-int((140737488355328*exp(-8187485477687969/(4398046511104*(20*heaviside(t - 2000) + 40*heaviside(t - 3000) - 390*heaviside(t - 14000) + 330*heaviside(t)))))/8301382342175545, t, 0, 1671787363946201/274877906944)^(4831891999187463/1125899906842624))*exp(-8187485477687969/1715238139330560)*int((140737488355328*exp(-8187485477687969/(4398046511104*(20*heaviside(t - 2000) + 40*heaviside(t - 3000) - 390*heaviside(t - 14000) + 330*heaviside(t)))))/8301382342175545, t, 0, 1671787363946201/274877906944)^(4268942045766151/562949953421312))/9487294105343480))
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답변 (1개)
Walter Roberson
2016년 1월 30일
All of those int() expressions are exactly the same. Pull that out of the expression and evaluate it and drop the result into the larger expression.
The result is about -2.546320960311438*10^28 by the way.
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