Scorers Gi function
Scorers Hi Function
斯科惹函數 (Scorers functions)是下列方程的兩個解
y
″
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x
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−
x
y
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1
π
{\displaystyle y''(x)-x\ y(x)={\frac {1}{\pi }}}
G
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=
1
π
∫
0
∞
sin
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t
3
3
+
x
t
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d
t
,
{\displaystyle \mathrm {Gi} (x)={\frac {1}{\pi }}\int _{0}^{\infty }\sin \left({\frac {t^{3}}{3}}+xt\right)\,dt,}
H
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1
π
∫
0
∞
exp
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−
t
3
3
+
x
t
)
d
t
.
{\displaystyle \mathrm {Hi} (x)={\frac {1}{\pi }}\int _{0}^{\infty }\exp \left(-{\frac {t^{3}}{3}}+xt\right)\,dt.}
也可以通過艾里函數 定義:
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B
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∫
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∞
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A
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∫
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B
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H
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∞
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d
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A
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∞
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{\displaystyle {\begin{aligned}\mathrm {Gi} (x)&{}=\mathrm {Bi} (x)\int _{x}^{\infty }\mathrm {Ai} (t)\,dt+\mathrm {Ai} (x)\int _{0}^{x}\mathrm {Bi} (t)\,dt,\\\mathrm {Hi} (x)&{}=\mathrm {Bi} (x)\int _{-\infty }^{x}\mathrm {Ai} (t)\,dt-\mathrm {Ai} (x)\int _{-\infty }^{x}\mathrm {Bi} (t)\,dt.\end{aligned}}}
冪級數展開
G
i
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z
)
=
∑
k
=
0
∞
c
o
s
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(
2
k
−
1
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∗
π
3
)
Γ
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k
+
1
3
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∗
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3
1
/
3
∗
z
)
k
k
!
{\displaystyle Gi(z)=\sum _{k=0}^{\infty }cos({\frac {(2k-1)*\pi }{3}})\Gamma ({\frac {k+1}{3}})*{\frac {(3^{1/3}*z)^{k}}{k!}}}
H
i
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z
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=
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−
2
/
3
π
∑
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∞
Γ
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2
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1
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∗
π
3
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3
1
/
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∗
z
)
k
k
!
{\displaystyle Hi(z)={\frac {3^{-2/3}}{\pi }}\sum _{k=0}^{\infty }\Gamma ({\frac {(2k+1)*\pi }{3}}{\bigr )}{\frac {(3^{1/3}*z)^{k}}{k!}}}
參考文獻
Olver, F. W. J., Scorer functions , Olver, Frank W. J. ; Lozier, Daniel M.; Boisvert, Ronald F.; Clark, Charles W. (編), NIST Handbook of Mathematical Functions , Cambridge University Press, 2010, ISBN 978-0521192255 , MR 2723248
Scorer, R. S., Numerical evaluation of integrals of the form
I
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∫
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1
x
2
f
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x
)
e
i
ϕ
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x
)
d
x
{\displaystyle I=\int _{x_{1}}^{x_{2}}f(x)e^{i\phi (x)}dx}
and the tabulation of the function
G
i
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z
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=
1
π
∫
0
∞
s
i
n
(
u
z
+
1
3
u
3
)
d
u
{\displaystyle {\rm {Gi}}(z)={\frac {1}{\pi }}\int _{0}^{\infty }{\rm {sin}}\left(uz+{\frac {1}{3}}u^{3}\right)du}
, The Quarterly Journal of Mechanics and Applied Mathematics, 1950, 3 : 107–112, ISSN 0033-5614 , MR 0037604 , doi:10.1093/qjmam/3.1.107