qbasic代码8

ncount2=1
jj=0
mg=M1
GOTO machfunc
it3cont1:
ncount2=ncount2+1
jj=1
xsav=xdum
M2=M1+(M1-lmach)
mg=M2: GOTO machfunc
it3cont2:
IF (xsav * xdum)<0! THEN GOTO bisect
M1 =M2 : GOTO it3cont1
bisect:
jj=jj+1
mlo = M1 : mhi =M2
itloop1:
mg = (mhi+mlo)*.5
jjj=0
GOTO machfunc
it1cont1:
jj=jj+1
IF ABS(xdum) < epps GOTO endloop3
jjj=1
msave = mg
xsav = xdum
mg = mlo: GOTO machfunc
it1cont2:
IF xsav*xdum < 0! THEN mhi = msave ELSE mlo= msave
IF jj>50 THEN PRINT" max. iteration stop criteria, jj = "; jj
IF jj>50 THEN PRINT"M2, msave :"; mg, msave
IF jj>50 THEN PRINT"continue ? ":STOP
GOTO itloop1