21 lines
587 B
Fortran
21 lines
587 B
Fortran
SUBROUTINE qromb(func,a,b,ss)
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INTEGER JMAX,JMAXP,K,KM
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REAL a,b,func,ss,EPS
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EXTERNAL func
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PARAMETER (EPS=1.e-6, JMAX=20, JMAXP=JMAX+1, K=5, KM=K-1)
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CU USES polint,trapzd
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INTEGER j
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REAL dss,h(JMAXP),s(JMAXP)
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h(1)=1.
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do 11 j=1,JMAX
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call trapzd(func,a,b,s(j),j)
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if (j.ge.K) then
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call polint(h(j-KM),s(j-KM),K,0.,ss,dss)
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if (abs(dss).le.EPS*abs(ss)) return
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endif
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s(j+1)=s(j)
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h(j+1)=0.25*h(j)
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11 continue
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pause 'too many steps in qromb'
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END
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