############################################################
# Building 'tbisect' and sample output on SGIs
#
# 'tbisect' is set up to compute sqrt(a) via bisection.
############################################################

einstein% pwd ; ls
/usr2/people/phy329/nonlin/ex1
Makefile    bisect.f    comf.inc    tbisect.f

einstein% make 
        f77 -g -c tbisect.f
        f77 -g -c bisect.f
        f77 -g -L/usr/local/lib tbisect.o bisect.o -lp329f -o tbisect

einstein% tbisect
 usage: tbisect <a> <xmin> <xmax> [<xtol> <trace>]

einstein% tbisect 2.0 1.0 2.0
    2.000000000000000       1.414213564246893      5.2999009625409599E-09

einstein% tbisect 2.0 1.0 2.0 1.0e-12
    2.000000000000000       1.414213562372879     -6.1084470814876113E-13

############################################################
# Enable tracing output by supplying 5th argument.  Note 
# supplying a '.' as an argument parsed by 'i4arg' or 'r8arg'
# is equivalent to specifying the default value. 
############################################################
einstein% tbisect 2.0 1.0 2.0 . 1
    1.000000000000000       2.000000000000000      0.2500000000000000    
    1.000000000000000       1.500000000000000     -0.4375000000000000    
    1.250000000000000       1.500000000000000     -0.1093750000000000    
    1.375000000000000       1.500000000000000      6.6406250000000000E-02
    1.375000000000000       1.437500000000000     -2.2460937500000000E-02
    1.406250000000000       1.437500000000000      2.1728515625000000E-02
    1.406250000000000       1.421875000000000     -4.2724609375000000E-04
    1.414062500000000       1.421875000000000      1.0635375976562500E-02
    1.414062500000000       1.417968750000000      5.1002502441406250E-03
    1.414062500000000       1.416015625000000      2.3355484008789062E-03
    1.414062500000000       1.415039062500000      9.5391273498535156E-04
    1.414062500000000       1.414550781250000      2.6327371597290039E-04
    1.414062500000000       1.414306640625000     -8.2001090049743652E-05
    1.414184570312500       1.414306640625000      9.0632587671279907E-05
    1.414184570312500       1.414245605468750      4.3148174881935120E-06
    1.414184570312500       1.414215087890625     -3.8843369111418724E-05
    1.414199829101562       1.414215087890625     -1.7264334019273520E-05
    1.414207458496094       1.414215087890625     -6.4747728174552321E-06
    1.414211273193359       1.414215087890625     -1.0799813026096672E-06
    1.414213180541992       1.414215087890625      1.6174171832972206E-06
    1.414213180541992       1.414214134216309      2.6871771297010127E-07
    1.414213180541992       1.414213657379150     -4.0563185166320181E-07
    1.414213418960571       1.414213657379150     -6.8457083557404985E-08
    1.414213538169861       1.414213657379150      1.0013031115363447E-07
    1.414213538169861       1.414213597774506      1.5836612909936321E-08
    1.414213538169861       1.414213567972183     -2.6310235545778937E-08
    1.414213553071022       1.414213567972183     -5.2368114289436107E-09
    1.414213560521603       1.414213567972183      5.2999009625409599E-09

    2.000000000000000       1.414213564246893      5.2999009625409599E-09