function [ xtab, weight ] = legendre_set ( norder )

%% LEGENDRE_SET sets abscissas and weights for Gauss-Legendre quadrature.
%
%  Integration region:
%
%    [ -1, 1 ]
%
%  Weight function:
%
%    1.0E+00
%
%  Integral to approximate:
%
%    Integral ( -1 <= X <= 1 ) F(X) dX
%
%  Approximate integral:
%
%    Sum ( 1 <= I <= NORDER ) WEIGHT(I) * F ( XTAB(I) )
%
%  Precision:
%
%    The quadrature rule will integrate exactly all polynomials up to
%    X**(2*NORDER-1).
%
%  Note:
%
%    The abscissas of the rule are the zeroes of the Legendre polynomial
%    P(NORDER)(X).
%
%    The integral produced by a Gauss-Legendre rule is equal to the
%    integral of the unique polynomial of degree NORDER-1 which
%    agrees with the function at the NORDER abscissas of the rule.
%
%  Licensing:
%
%    This code is distributed under the GNU LGPL license. 
%
%  Modified:
%
%    25 November 2004
%
%  Author:
%
%    John Burkardt
%
%  Reference:
%
%    Abramowitz and Stegun,
%    Handbook of Mathematical Functions,
%    National Bureau of Standards, 1964.
%
%    Vladimir Krylov,
%    Approximate Calculation of Integrals,
%    MacMillan, 1962.
%
%    Arthur Stroud and Don Secrest,
%    Gaussian Quadrature Formulas,
%    Prentice Hall, 1966.
%
%    Daniel Zwillinger, editor,
%    Standard Mathematical Tables and Formulae,
%    30th Edition,
%    CRC Press, 1996.
%
%  Parameters:
%
%    Input, integer NORDER, the order of the rule.
%    NORDER must be between 1 and 20, 32 or 64.
%
%    Output, real XTAB(NORDER), the abscissas of the rule.
%
%    Output, real WEIGHT(NORDER), the weights of the rule.
%    The weights are positive, symmetric and should sum to 2.
%
  if ( norder == 1 )

    xtab(1) =   0.0E+00;

    weight(1) = 2.0E+00;

  elseif ( norder == 2 )

    xtab(1) = - 0.577350269189625764509148780502E+00;
    xtab(2) =   0.577350269189625764509148780502E+00;

    weight(1) = 1.0E+00;
    weight(2) = 1.0E+00;

  elseif ( norder == 3 )

    xtab(1) = - 0.774596669241483377035853079956E+00;
    xtab(2) =   0.0E+00;
    xtab(3) =   0.774596669241483377035853079956E+00;

    weight(1) = 5.0E+00 / 9.0E+00;
    weight(2) = 8.0E+00 / 9.0E+00;
    weight(3) = 5.0E+00 / 9.0E+00;

  elseif ( norder == 4 )

    xtab(1) = - 0.861136311594052575223946488893E+00;
    xtab(2) = - 0.339981043584856264802665759103E+00;
    xtab(3) =   0.339981043584856264802665759103E+00;
    xtab(4) =   0.861136311594052575223946488893E+00;

    weight(1) = 0.347854845137453857373063949222E+00;
    weight(2) = 0.652145154862546142626936050778E+00;
    weight(3) = 0.652145154862546142626936050778E+00;
    weight(4) = 0.347854845137453857373063949222E+00;

  elseif ( norder == 5 )

    xtab(1) = - 0.906179845938663992797626878299E+00;
    xtab(2) = - 0.538469310105683091036314420700E+00;
    xtab(3) =   0.0E+00;
    xtab(4) =   0.538469310105683091036314420700E+00;
    xtab(5) =   0.906179845938663992797626878299E+00;

    weight(1) = 0.236926885056189087514264040720E+00;
    weight(2) = 0.478628670499366468041291514836E+00;
    weight(3) = 0.568888888888888888888888888889E+00;
    weight(4) = 0.478628670499366468041291514836E+00;
    weight(5) = 0.236926885056189087514264040720E+00;

  elseif ( norder == 6 )

    xtab(1) = - 0.932469514203152027812301554494E+00;
    xtab(2) = - 0.661209386466264513661399595020E+00;
    xtab(3) = - 0.238619186083196908630501721681E+00;
    xtab(4) =   0.238619186083196908630501721681E+00;
    xtab(5) =   0.661209386466264513661399595020E+00;
    xtab(6) =   0.932469514203152027812301554494E+00;

    weight(1) = 0.171324492379170345040296142173E+00;
    weight(2) = 0.360761573048138607569833513838E+00;
    weight(3) = 0.467913934572691047389870343990E+00;
    weight(4) = 0.467913934572691047389870343990E+00;
    weight(5) = 0.360761573048138607569833513838E+00;
    weight(6) = 0.171324492379170345040296142173E+00;

  elseif ( norder == 7 )

    xtab(1) = - 0.949107912342758524526189684048E+00;
    xtab(2) = - 0.741531185599394439863864773281E+00;
    xtab(3) = - 0.405845151377397166906606412077E+00;
    xtab(4) =   0.0E+00;
    xtab(5) =   0.405845151377397166906606412077E+00;
    xtab(6) =   0.741531185599394439863864773281E+00;
    xtab(7) =   0.949107912342758524526189684048E+00;

    weight(1) = 0.129484966168869693270611432679E+00;
    weight(2) = 0.279705391489276667901467771424E+00;
    weight(3) = 0.381830050505118944950369775489E+00;
    weight(4) = 0.417959183673469387755102040816E+00;
    weight(5) = 0.381830050505118944950369775489E+00;
    weight(6) = 0.279705391489276667901467771424E+00;
    weight(7) = 0.129484966168869693270611432679E+00;

  elseif ( norder == 8 )

    xtab(1) = - 0.960289856497536231683560868569E+00;
    xtab(2) = - 0.796666477413626739591553936476E+00;
    xtab(3) = - 0.525532409916328985817739049189E+00;
    xtab(4) = - 0.183434642495649804939476142360E+00;
    xtab(5) =   0.183434642495649804939476142360E+00;
    xtab(6) =   0.525532409916328985817739049189E+00;
    xtab(7) =   0.796666477413626739591553936476E+00;
    xtab(8) =   0.960289856497536231683560868569E+00;

    weight(1) = 0.101228536290376259152531354310E+00;
    weight(2) = 0.222381034453374470544355994426E+00;
    weight(3) = 0.313706645877887287337962201987E+00;
    weight(4) = 0.362683783378361982965150449277E+00;
    weight(5) = 0.362683783378361982965150449277E+00;
    weight(6) = 0.313706645877887287337962201987E+00;
    weight(7) = 0.222381034453374470544355994426E+00;
    weight(8) = 0.101228536290376259152531354310E+00;

  elseif ( norder == 9 )

    xtab(1) = - 0.968160239507626089835576202904E+00;
    xtab(2) = - 0.836031107326635794299429788070E+00;
    xtab(3) = - 0.613371432700590397308702039341E+00;
    xtab(4) = - 0.324253423403808929038538014643E+00;
    xtab(5) =   0.0E+00;
    xtab(6) =   0.324253423403808929038538014643E+00;
    xtab(7) =   0.613371432700590397308702039341E+00;
    xtab(8) =   0.836031107326635794299429788070E+00;
    xtab(9) =   0.968160239507626089835576202904E+00;

    weight(1) = 0.812743883615744119718921581105E-01;
    weight(2) = 0.180648160694857404058472031243E+00;
    weight(3) = 0.260610696402935462318742869419E+00;
    weight(4) = 0.312347077040002840068630406584E+00;
    weight(5) = 0.330239355001259763164525069287E+00;
    weight(6) = 0.312347077040002840068630406584E+00;
    weight(7) = 0.260610696402935462318742869419E+00;
    weight(8) = 0.180648160694857404058472031243E+00;
    weight(9) = 0.812743883615744119718921581105E-01;

  elseif ( norder == 10 )

    xtab(1) =  - 0.973906528517171720077964012084E+00;
    xtab(2) =  - 0.865063366688984510732096688423E+00;
    xtab(3) =  - 0.679409568299024406234327365115E+00;
    xtab(4) =  - 0.433395394129247190799265943166E+00;
    xtab(5) =  - 0.148874338981631210884826001130E+00;
    xtab(6) =    0.148874338981631210884826001130E+00;
    xtab(7) =    0.433395394129247190799265943166E+00;
    xtab(8) =    0.679409568299024406234327365115E+00;
    xtab(9) =    0.865063366688984510732096688423E+00;
    xtab(10) =   0.973906528517171720077964012084E+00;

    weight(1) =  0.666713443086881375935688098933E-01;
    weight(2) =  0.149451349150580593145776339658E+00;
    weight(3) =  0.219086362515982043995534934228E+00;
    weight(4) =  0.269266719309996355091226921569E+00;
    weight(5) =  0.295524224714752870173892994651E+00;
    weight(6) =  0.295524224714752870173892994651E+00;
    weight(7) =  0.269266719309996355091226921569E+00;
    weight(8) =  0.219086362515982043995534934228E+00;
    weight(9) =  0.149451349150580593145776339658E+00;
    weight(10) = 0.666713443086881375935688098933E-01;

  elseif ( norder == 11 )

    xtab(1) =  - 0.978228658146056992803938001123E+00;
    xtab(2) =  - 0.887062599768095299075157769304E+00;
    xtab(3) =  - 0.730152005574049324093416252031E+00;
    xtab(4) =  - 0.519096129206811815925725669459E+00;
    xtab(5) =  - 0.269543155952344972331531985401E+00;
    xtab(6) =    0.0E+00;
    xtab(7) =    0.269543155952344972331531985401E+00;
    xtab(8) =    0.519096129206811815925725669459E+00;
    xtab(9) =    0.730152005574049324093416252031E+00;
    xtab(10) =   0.887062599768095299075157769304E+00;
    xtab(11) =   0.978228658146056992803938001123E+00;

    weight(1) =  0.556685671161736664827537204425E-01;
    weight(2) =  0.125580369464904624634694299224E+00;
    weight(3) =  0.186290210927734251426097641432E+00;
    weight(4) =  0.233193764591990479918523704843E+00;
    weight(5) =  0.262804544510246662180688869891E+00;
    weight(6) =  0.272925086777900630714483528336E+00;
    weight(7) =  0.262804544510246662180688869891E+00;
    weight(8) =  0.233193764591990479918523704843E+00;
    weight(9) =  0.186290210927734251426097641432E+00;
    weight(10) = 0.125580369464904624634694299224E+00;
    weight(11) = 0.556685671161736664827537204425E-01;

  elseif ( norder == 12 )

    xtab(1) =  - 0.981560634246719250690549090149E+00;
    xtab(2) =  - 0.904117256370474856678465866119E+00;
    xtab(3) =  - 0.769902674194304687036893833213E+00;
    xtab(4) =  - 0.587317954286617447296702418941E+00;
    xtab(5) =  - 0.367831498998180193752691536644E+00;
    xtab(6) =  - 0.125233408511468915472441369464E+00;
    xtab(7) =    0.125233408511468915472441369464E+00;
    xtab(8) =    0.367831498998180193752691536644E+00;
    xtab(9) =    0.587317954286617447296702418941E+00;
    xtab(10) =   0.769902674194304687036893833213E+00;
    xtab(11) =   0.904117256370474856678465866119E+00;
    xtab(12) =   0.981560634246719250690549090149E+00;

    weight(1) =  0.471753363865118271946159614850E-01;
    weight(2) =  0.106939325995318430960254718194E+00;
    weight(3) =  0.160078328543346226334652529543E+00;
    weight(4) =  0.203167426723065921749064455810E+00;
    weight(5) =  0.233492536538354808760849898925E+00;
    weight(6) =  0.249147045813402785000562436043E+00;
    weight(7) =  0.249147045813402785000562436043E+00;
    weight(8) =  0.233492536538354808760849898925E+00;
    weight(9) =  0.203167426723065921749064455810E+00;
    weight(10) = 0.160078328543346226334652529543E+00;
    weight(11) = 0.106939325995318430960254718194E+00;
    weight(12) = 0.471753363865118271946159614850E-01;

  elseif ( norder == 13 )

    xtab(1) =  - 0.984183054718588149472829448807E+00;
    xtab(2) =  - 0.917598399222977965206547836501E+00;
    xtab(3) =  - 0.801578090733309912794206489583E+00;
    xtab(4) =  - 0.642349339440340220643984606996E+00;
    xtab(5) =  - 0.448492751036446852877912852128E+00;
    xtab(6) =  - 0.230458315955134794065528121098E+00;
    xtab(7) =    0.0E+00;
    xtab(8) =    0.230458315955134794065528121098E+00;
    xtab(9) =    0.448492751036446852877912852128E+00;
    xtab(10) =   0.642349339440340220643984606996E+00;
    xtab(11) =   0.801578090733309912794206489583E+00;
    xtab(12) =   0.917598399222977965206547836501E+00;
    xtab(13) =   0.984183054718588149472829448807E+00;

    weight(1) =  0.404840047653158795200215922010E-01;
    weight(2) =  0.921214998377284479144217759538E-01;
    weight(3) =  0.138873510219787238463601776869E+00;
    weight(4) =  0.178145980761945738280046691996E+00;
    weight(5) =  0.207816047536888502312523219306E+00;
    weight(6) =  0.226283180262897238412090186040E+00;
    weight(7) =  0.232551553230873910194589515269E+00;
    weight(8) =  0.226283180262897238412090186040E+00;
    weight(9) =  0.207816047536888502312523219306E+00;
    weight(10) = 0.178145980761945738280046691996E+00;
    weight(11) = 0.138873510219787238463601776869E+00;
    weight(12) = 0.921214998377284479144217759538E-01;
    weight(13) = 0.404840047653158795200215922010E-01;

  elseif ( norder == 14 )

    xtab(1) =  - 0.986283808696812338841597266704E+00;
    xtab(2) =  - 0.928434883663573517336391139378E+00;
    xtab(3) =  - 0.827201315069764993189794742650E+00;
    xtab(4) =  - 0.687292904811685470148019803019E+00;
    xtab(5) =  - 0.515248636358154091965290718551E+00;
    xtab(6) =  - 0.319112368927889760435671824168E+00;
    xtab(7) =  - 0.108054948707343662066244650220E+00;
    xtab(8) =    0.108054948707343662066244650220E+00;
    xtab(9) =    0.319112368927889760435671824168E+00;
    xtab(10) =   0.515248636358154091965290718551E+00;
    xtab(11) =   0.687292904811685470148019803019E+00;
    xtab(12) =   0.827201315069764993189794742650E+00;
    xtab(13) =   0.928434883663573517336391139378E+00;
    xtab(14) =   0.986283808696812338841597266704E+00;

    weight(1) =  0.351194603317518630318328761382E-01;
    weight(2) =  0.801580871597602098056332770629E-01;
    weight(3) =  0.121518570687903184689414809072E+00;
    weight(4) =  0.157203167158193534569601938624E+00;
    weight(5) =  0.185538397477937813741716590125E+00;
    weight(6) =  0.205198463721295603965924065661E+00;
    weight(7) =  0.215263853463157790195876443316E+00;
    weight(8) =  0.215263853463157790195876443316E+00;
    weight(9) =  0.205198463721295603965924065661E+00;
    weight(10) = 0.185538397477937813741716590125E+00;
    weight(11) = 0.157203167158193534569601938624E+00;
    weight(12) = 0.121518570687903184689414809072E+00;
    weight(13) = 0.801580871597602098056332770629E-01;
    weight(14) = 0.351194603317518630318328761382E-01;

  elseif ( norder == 15 )

    xtab(1) =  - 0.987992518020485428489565718587E+00;
    xtab(2) =  - 0.937273392400705904307758947710E+00;
    xtab(3) =  - 0.848206583410427216200648320774E+00;
    xtab(4) =  - 0.724417731360170047416186054614E+00;
    xtab(5) =  - 0.570972172608538847537226737254E+00;
    xtab(6) =  - 0.394151347077563369897207370981E+00;
    xtab(7) =  - 0.201194093997434522300628303395E+00;
    xtab(8) =    0.0E+00;
    xtab(9) =    0.201194093997434522300628303395E+00;
    xtab(10) =   0.394151347077563369897207370981E+00;
    xtab(11) =   0.570972172608538847537226737254E+00;
    xtab(12) =   0.724417731360170047416186054614E+00;
    xtab(13) =   0.848206583410427216200648320774E+00;
    xtab(14) =   0.937273392400705904307758947710E+00;
    xtab(15) =   0.987992518020485428489565718587E+00;

    weight(1) =  0.307532419961172683546283935772E-01;
    weight(2) =  0.703660474881081247092674164507E-01;
    weight(3) =  0.107159220467171935011869546686E+00;
    weight(4) =  0.139570677926154314447804794511E+00;
    weight(5) =  0.166269205816993933553200860481E+00;
    weight(6) =  0.186161000015562211026800561866E+00;
    weight(7) =  0.198431485327111576456118326444E+00;
    weight(8) =  0.202578241925561272880620199968E+00;
    weight(9) =  0.198431485327111576456118326444E+00;
    weight(10) = 0.186161000015562211026800561866E+00;
    weight(11) = 0.166269205816993933553200860481E+00;
    weight(12) = 0.139570677926154314447804794511E+00;
    weight(13) = 0.107159220467171935011869546686E+00;
    weight(14) = 0.703660474881081247092674164507E-01;
    weight(15) = 0.307532419961172683546283935772E-01;

  elseif ( norder == 16 )

    xtab(1) =  - 0.989400934991649932596154173450E+00;
    xtab(2) =  - 0.944575023073232576077988415535E+00;
    xtab(3) =  - 0.865631202387831743880467897712E+00;
    xtab(4) =  - 0.755404408355003033895101194847E+00;
    xtab(5) =  - 0.617876244402643748446671764049E+00;
    xtab(6) =  - 0.458016777657227386342419442984E+00;
    xtab(7) =  - 0.281603550779258913230460501460E+00;
    xtab(8) =  - 0.950125098376374401853193354250E-01;
    xtab(9) =    0.950125098376374401853193354250E-01;
    xtab(10) =   0.281603550779258913230460501460E+00;
    xtab(11) =   0.458016777657227386342419442984E+00;
    xtab(12) =   0.617876244402643748446671764049E+00;
    xtab(13) =   0.755404408355003033895101194847E+00;
    xtab(14) =   0.865631202387831743880467897712E+00;
    xtab(15) =   0.944575023073232576077988415535E+00;
    xtab(16) =   0.989400934991649932596154173450E+00;

    weight(1) =  0.271524594117540948517805724560E-01;
    weight(2) =  0.622535239386478928628438369944E-01;
    weight(3) =  0.951585116824927848099251076022E-01;
    weight(4) =  0.124628971255533872052476282192E+00;
    weight(5) =  0.149595988816576732081501730547E+00;
    weight(6) =  0.169156519395002538189312079030E+00;
    weight(7) =  0.182603415044923588866763667969E+00;
    weight(8) =  0.189450610455068496285396723208E+00;
    weight(9) =  0.189450610455068496285396723208E+00;
    weight(10) = 0.182603415044923588866763667969E+00;
    weight(11) = 0.169156519395002538189312079030E+00;
    weight(12) = 0.149595988816576732081501730547E+00;
    weight(13) = 0.124628971255533872052476282192E+00;
    weight(14) = 0.951585116824927848099251076022E-01;
    weight(15) = 0.622535239386478928628438369944E-01;
    weight(16) = 0.271524594117540948517805724560E-01;

  elseif ( norder == 17 )

    xtab(1) =  - 0.990575475314417335675434019941E+00;
    xtab(2) =  - 0.950675521768767761222716957896E+00;
    xtab(3) =  - 0.880239153726985902122955694488E+00;
    xtab(4) =  - 0.781514003896801406925230055520E+00;
    xtab(5) =  - 0.657671159216690765850302216643E+00;
    xtab(6) =  - 0.512690537086476967886246568630E+00;
    xtab(7) =  - 0.351231763453876315297185517095E+00;
    xtab(8) =  - 0.178484181495847855850677493654E+00;
    xtab(9) =    0.0E+00;
    xtab(10) =   0.178484181495847855850677493654E+00;
    xtab(11) =   0.351231763453876315297185517095E+00;
    xtab(12) =   0.512690537086476967886246568630E+00;
    xtab(13) =   0.657671159216690765850302216643E+00;
    xtab(14) =   0.781514003896801406925230055520E+00;
    xtab(15) =   0.880239153726985902122955694488E+00;
    xtab(16) =   0.950675521768767761222716957896E+00;
    xtab(17) =   0.990575475314417335675434019941E+00;

    weight(1) =  0.241483028685479319601100262876E-01;
    weight(2) =  0.554595293739872011294401653582E-01;
    weight(3) =  0.850361483171791808835353701911E-01;
    weight(4) =  0.111883847193403971094788385626E+00;
    weight(5) =  0.135136368468525473286319981702E+00;
    weight(6) =  0.154045761076810288081431594802E+00;
    weight(7) =  0.168004102156450044509970663788E+00;
    weight(8) =  0.176562705366992646325270990113E+00;
    weight(9) =  0.179446470356206525458265644262E+00;
    weight(10) = 0.176562705366992646325270990113E+00;
    weight(11) = 0.168004102156450044509970663788E+00;
    weight(12) = 0.154045761076810288081431594802E+00;
    weight(13) = 0.135136368468525473286319981702E+00;
    weight(14) = 0.111883847193403971094788385626E+00;
    weight(15) = 0.850361483171791808835353701911E-01;
    weight(16) = 0.554595293739872011294401653582E-01;
    weight(17) = 0.241483028685479319601100262876E-01;

  elseif ( norder == 18 )

    xtab(1) =  - 0.991565168420930946730016004706E+00;
    xtab(2) =  - 0.955823949571397755181195892930E+00;
    xtab(3) =  - 0.892602466497555739206060591127E+00;
    xtab(4) =  - 0.803704958972523115682417455015E+00;
    xtab(5) =  - 0.691687043060353207874891081289E+00;
    xtab(6) =  - 0.559770831073947534607871548525E+00;
    xtab(7) =  - 0.411751161462842646035931793833E+00;
    xtab(8) =  - 0.251886225691505509588972854878E+00;
    xtab(9) =  - 0.847750130417353012422618529358E-01;
    xtab(10) =   0.847750130417353012422618529358E-01;
    xtab(11) =   0.251886225691505509588972854878E+00;
    xtab(12) =   0.411751161462842646035931793833E+00;
    xtab(13) =   0.559770831073947534607871548525E+00;
    xtab(14) =   0.691687043060353207874891081289E+00;
    xtab(15) =   0.803704958972523115682417455015E+00;
    xtab(16) =   0.892602466497555739206060591127E+00;
    xtab(17) =   0.955823949571397755181195892930E+00;
    xtab(18) =   0.991565168420930946730016004706E+00;

    weight(1) =  0.216160135264833103133427102665E-01;
    weight(2) =  0.497145488949697964533349462026E-01;
    weight(3) =  0.764257302548890565291296776166E-01;
    weight(4) =  0.100942044106287165562813984925E+00;
    weight(5) =  0.122555206711478460184519126800E+00;
    weight(6) =  0.140642914670650651204731303752E+00;
    weight(7) =  0.154684675126265244925418003836E+00;
    weight(8) =  0.164276483745832722986053776466E+00;
    weight(9) =  0.169142382963143591840656470135E+00;
    weight(10) = 0.169142382963143591840656470135E+00;
    weight(11) = 0.164276483745832722986053776466E+00;
    weight(12) = 0.154684675126265244925418003836E+00;
    weight(13) = 0.140642914670650651204731303752E+00;
    weight(14) = 0.122555206711478460184519126800E+00;
    weight(15) = 0.100942044106287165562813984925E+00;
    weight(16) = 0.764257302548890565291296776166E-01;
    weight(17) = 0.497145488949697964533349462026E-01;
    weight(18) = 0.216160135264833103133427102665E-01;

  elseif ( norder == 19 )

    xtab(1) =  - 0.992406843843584403189017670253E+00;
    xtab(2) =  - 0.960208152134830030852778840688E+00;
    xtab(3) =  - 0.903155903614817901642660928532E+00;
    xtab(4) =  - 0.822714656537142824978922486713E+00;
    xtab(5) =  - 0.720966177335229378617095860824E+00;
    xtab(6) =  - 0.600545304661681023469638164946E+00;
    xtab(7) =  - 0.464570741375960945717267148104E+00;
    xtab(8) =  - 0.316564099963629831990117328850E+00;
    xtab(9) =  - 0.160358645640225375868096115741E+00;
    xtab(10) =   0.0E+00;
    xtab(11) =   0.160358645640225375868096115741E+00;
    xtab(12) =   0.316564099963629831990117328850E+00;
    xtab(13) =   0.464570741375960945717267148104E+00;
    xtab(14) =   0.600545304661681023469638164946E+00;
    xtab(15) =   0.720966177335229378617095860824E+00;
    xtab(16) =   0.822714656537142824978922486713E+00;
    xtab(17) =   0.903155903614817901642660928532E+00;
    xtab(18) =   0.960208152134830030852778840688E+00;
    xtab(19) =   0.992406843843584403189017670253E+00;

    weight(1) =  0.194617882297264770363120414644E-01;
    weight(2) =  0.448142267656996003328381574020E-01;
    weight(3) =  0.690445427376412265807082580060E-01;
    weight(4) =  0.914900216224499994644620941238E-01;
    weight(5) =  0.111566645547333994716023901682E+00;
    weight(6) =  0.128753962539336227675515784857E+00;
    weight(7) =  0.142606702173606611775746109442E+00;
    weight(8) =  0.152766042065859666778855400898E+00;
    weight(9) =  0.158968843393954347649956439465E+00;
    weight(10) = 0.161054449848783695979163625321E+00;
    weight(11) = 0.158968843393954347649956439465E+00;
    weight(12) = 0.152766042065859666778855400898E+00;
    weight(13) = 0.142606702173606611775746109442E+00;
    weight(14) = 0.128753962539336227675515784857E+00;
    weight(15) = 0.111566645547333994716023901682E+00;
    weight(16) = 0.914900216224499994644620941238E-01;
    weight(17) = 0.690445427376412265807082580060E-01;
    weight(18) = 0.448142267656996003328381574020E-01;
    weight(19) = 0.194617882297264770363120414644E-01;

  elseif ( norder == 20 )

    xtab(1) =  - 0.993128599185094924786122388471E+00;
    xtab(2) =  - 0.963971927277913791267666131197E+00;
    xtab(3) =  - 0.912234428251325905867752441203E+00;
    xtab(4) =  - 0.839116971822218823394529061702E+00;
    xtab(5) =  - 0.746331906460150792614305070356E+00;
    xtab(6) =  - 0.636053680726515025452836696226E+00;
    xtab(7) =  - 0.510867001950827098004364050955E+00;
    xtab(8) =  - 0.373706088715419560672548177025E+00;
    xtab(9) =  - 0.227785851141645078080496195369E+00;
    xtab(10) = - 0.765265211334973337546404093988E-01;
    xtab(11) =   0.765265211334973337546404093988E-01;
    xtab(12) =   0.227785851141645078080496195369E+00;
    xtab(13) =   0.373706088715419560672548177025E+00;
    xtab(14) =   0.510867001950827098004364050955E+00;
    xtab(15) =   0.636053680726515025452836696226E+00;
    xtab(16) =   0.746331906460150792614305070356E+00;
    xtab(17) =   0.839116971822218823394529061702E+00;
    xtab(18) =   0.912234428251325905867752441203E+00;
    xtab(19) =   0.963971927277913791267666131197E+00;
    xtab(20) =   0.993128599185094924786122388471E+00;

    weight(1) =  0.176140071391521183118619623519E-01;
    weight(2) =  0.406014298003869413310399522749E-01;
    weight(3) =  0.626720483341090635695065351870E-01;
    weight(4) =  0.832767415767047487247581432220E-01;
    weight(5) =  0.101930119817240435036750135480E+00;
    weight(6) =  0.118194531961518417312377377711E+00;
    weight(7) =  0.131688638449176626898494499748E+00;
    weight(8) =  0.142096109318382051329298325067E+00;
    weight(9) =  0.149172986472603746787828737002E+00;
    weight(10) = 0.152753387130725850698084331955E+00;
    weight(11) = 0.152753387130725850698084331955E+00;
    weight(12) = 0.149172986472603746787828737002E+00;
    weight(13) = 0.142096109318382051329298325067E+00;
    weight(14) = 0.131688638449176626898494499748E+00;
    weight(15) = 0.118194531961518417312377377711E+00;
    weight(16) = 0.101930119817240435036750135480E+00;
    weight(17) = 0.832767415767047487247581432220E-01;
    weight(18) = 0.626720483341090635695065351870E-01;
    weight(19) = 0.406014298003869413310399522749E-01;
    weight(20) = 0.176140071391521183118619623519E-01;

  elseif ( norder == 32 )

    xtab(1) =  - 0.997263861849481563544981128665E+00;
    xtab(2) =  - 0.985611511545268335400175044631E+00;
    xtab(3) =  - 0.964762255587506430773811928118E+00;
    xtab(4) =  - 0.934906075937739689170919134835E+00;
    xtab(5) =  - 0.896321155766052123965307243719E+00;
    xtab(6) =  - 0.849367613732569970133693004968E+00;
    xtab(7) =  - 0.794483795967942406963097298970E+00;
    xtab(8) =  - 0.732182118740289680387426665091E+00;
    xtab(9) =  - 0.663044266930215200975115168663E+00;
    xtab(10) = - 0.587715757240762329040745476402E+00;
    xtab(11) = - 0.506899908932229390023747474378E+00;
    xtab(12) = - 0.421351276130635345364119436172E+00;
    xtab(13) = - 0.331868602282127649779916805730E+00;
    xtab(14) = - 0.239287362252137074544603209166E+00;
    xtab(15) = - 0.144471961582796493485186373599E+00;
    xtab(16) = - 0.483076656877383162348125704405E-01;
    xtab(17) =   0.483076656877383162348125704405E-01;
    xtab(18) =   0.144471961582796493485186373599E+00;
    xtab(19) =   0.239287362252137074544603209166E+00;
    xtab(20) =   0.331868602282127649779916805730E+00;
    xtab(21) =   0.421351276130635345364119436172E+00;
    xtab(22) =   0.506899908932229390023747474378E+00;
    xtab(23) =   0.587715757240762329040745476402E+00;
    xtab(24) =   0.663044266930215200975115168663E+00;
    xtab(25) =   0.732182118740289680387426665091E+00;
    xtab(26) =   0.794483795967942406963097298970E+00;
    xtab(27) =   0.849367613732569970133693004968E+00;
    xtab(28) =   0.896321155766052123965307243719E+00;
    xtab(29) =   0.934906075937739689170919134835E+00;
    xtab(30) =   0.964762255587506430773811928118E+00;
    xtab(31) =   0.985611511545268335400175044631E+00;
    xtab(32) =   0.997263861849481563544981128665E+00;

    weight(1) =  0.701861000947009660040706373885E-02;
    weight(2) =  0.162743947309056706051705622064E-01;
    weight(3) =  0.253920653092620594557525897892E-01;
    weight(4) =  0.342738629130214331026877322524E-01;
    weight(5) =  0.428358980222266806568786466061E-01;
    weight(6) =  0.509980592623761761961632446895E-01;
    weight(7) =  0.586840934785355471452836373002E-01;
    weight(8) =  0.658222227763618468376500637069E-01;
    weight(9) =  0.723457941088485062253993564785E-01;
    weight(10) = 0.781938957870703064717409188283E-01;
    weight(11) = 0.833119242269467552221990746043E-01;
    weight(12) = 0.876520930044038111427714627518E-01;
    weight(13) = 0.911738786957638847128685771116E-01;
    weight(14) = 0.938443990808045656391802376681E-01;
    weight(15) = 0.956387200792748594190820022041E-01;
    weight(16) = 0.965400885147278005667648300636E-01;
    weight(17) = 0.965400885147278005667648300636E-01;
    weight(18) = 0.956387200792748594190820022041E-01;
    weight(19) = 0.938443990808045656391802376681E-01;
    weight(20) = 0.911738786957638847128685771116E-01;
    weight(21) = 0.876520930044038111427714627518E-01;
    weight(22) = 0.833119242269467552221990746043E-01;
    weight(23) = 0.781938957870703064717409188283E-01;
    weight(24) = 0.723457941088485062253993564785E-01;
    weight(25) = 0.658222227763618468376500637069E-01;
    weight(26) = 0.586840934785355471452836373002E-01;
    weight(27) = 0.509980592623761761961632446895E-01;
    weight(28) = 0.428358980222266806568786466061E-01;
    weight(29) = 0.342738629130214331026877322524E-01;
    weight(30) = 0.253920653092620594557525897892E-01;
    weight(31) = 0.162743947309056706051705622064E-01;
    weight(32) = 0.701861000947009660040706373885E-02;

  elseif ( norder == 64 )

    xtab(1) =  - 0.999305041735772139456905624346E+00;
    xtab(2) =  - 0.996340116771955279346924500676E+00;
    xtab(3) =  - 0.991013371476744320739382383443E+00;
    xtab(4) =  - 0.983336253884625956931299302157E+00;
    xtab(5) =  - 0.973326827789910963741853507352E+00;
    xtab(6) =  - 0.961008799652053718918614121897E+00;
    xtab(7) =  - 0.946411374858402816062481491347E+00;
    xtab(8) =  - 0.929569172131939575821490154559E+00;
    xtab(9) =  - 0.910522137078502805756380668008E+00;
    xtab(10) = - 0.889315445995114105853404038273E+00;
    xtab(11) = - 0.865999398154092819760783385070E+00;
    xtab(12) = - 0.840629296252580362751691544696E+00;
    xtab(13) = - 0.813265315122797559741923338086E+00;
    xtab(14) = - 0.783972358943341407610220525214E+00;
    xtab(15) = - 0.752819907260531896611863774886E+00;
    xtab(16) = - 0.719881850171610826848940217832E+00;
    xtab(17) = - 0.685236313054233242563558371031E+00;
    xtab(18) = - 0.648965471254657339857761231993E+00;
    xtab(19) = - 0.611155355172393250248852971019E+00;
    xtab(20) = - 0.571895646202634034283878116659E+00;
    xtab(21) = - 0.531279464019894545658013903544E+00;
    xtab(22) = - 0.489403145707052957478526307022E+00;
    xtab(23) = - 0.446366017253464087984947714759E+00;
    xtab(24) = - 0.402270157963991603695766771260E+00;
    xtab(25) = - 0.357220158337668115950442615046E+00;
    xtab(26) = - 0.311322871990210956157512698560E+00;
    xtab(27) = - 0.264687162208767416373964172510E+00;
    xtab(28) = - 0.217423643740007084149648748989E+00;
    xtab(29) = - 0.169644420423992818037313629748E+00;
    xtab(30) = - 0.121462819296120554470376463492E+00;
    xtab(31) = - 0.729931217877990394495429419403E-01;
    xtab(32) = - 0.243502926634244325089558428537E-01;
    xtab(33) =   0.243502926634244325089558428537E-01;
    xtab(34) =   0.729931217877990394495429419403E-01;
    xtab(35) =   0.121462819296120554470376463492E+00;
    xtab(36) =   0.169644420423992818037313629748E+00;
    xtab(37) =   0.217423643740007084149648748989E+00;
    xtab(38) =   0.264687162208767416373964172510E+00;
    xtab(39) =   0.311322871990210956157512698560E+00;
    xtab(40) =   0.357220158337668115950442615046E+00;
    xtab(41) =   0.402270157963991603695766771260E+00;
    xtab(42) =   0.446366017253464087984947714759E+00;
    xtab(43) =   0.489403145707052957478526307022E+00;
    xtab(44) =   0.531279464019894545658013903544E+00;
    xtab(45) =   0.571895646202634034283878116659E+00;
    xtab(46) =   0.611155355172393250248852971019E+00;
    xtab(47) =   0.648965471254657339857761231993E+00;
    xtab(48) =   0.685236313054233242563558371031E+00;
    xtab(49) =   0.719881850171610826848940217832E+00;
    xtab(50) =   0.752819907260531896611863774886E+00;
    xtab(51) =   0.783972358943341407610220525214E+00;
    xtab(52) =   0.813265315122797559741923338086E+00;
    xtab(53) =   0.840629296252580362751691544696E+00;
    xtab(54) =   0.865999398154092819760783385070E+00;
    xtab(55) =   0.889315445995114105853404038273E+00;
    xtab(56) =   0.910522137078502805756380668008E+00;
    xtab(57) =   0.929569172131939575821490154559E+00;
    xtab(58) =   0.946411374858402816062481491347E+00;
    xtab(59) =   0.961008799652053718918614121897E+00;
    xtab(60) =   0.973326827789910963741853507352E+00;
    xtab(61) =   0.983336253884625956931299302157E+00;
    xtab(62) =   0.991013371476744320739382383443E+00;
    xtab(63) =   0.996340116771955279346924500676E+00;
    xtab(64) =   0.999305041735772139456905624346E+00;

    weight(1) =  0.178328072169643294729607914497E-02;
    weight(2) =  0.414703326056246763528753572855E-02;
    weight(3) =  0.650445796897836285611736039998E-02;
    weight(4) =  0.884675982636394772303091465973E-02;
    weight(5) =  0.111681394601311288185904930192E-01;
    weight(6) =  0.134630478967186425980607666860E-01;
    weight(7) =  0.157260304760247193219659952975E-01;
    weight(8) =  0.179517157756973430850453020011E-01;
    weight(9) =  0.201348231535302093723403167285E-01;
    weight(10) = 0.222701738083832541592983303842E-01;
    weight(11) = 0.243527025687108733381775504091E-01;
    weight(12) = 0.263774697150546586716917926252E-01;
    weight(13) = 0.283396726142594832275113052002E-01;
    weight(14) = 0.302346570724024788679740598195E-01;
    weight(15) = 0.320579283548515535854675043479E-01;
    weight(16) = 0.338051618371416093915654821107E-01;
    weight(17) = 0.354722132568823838106931467152E-01;
    weight(18) = 0.370551285402400460404151018096E-01;
    weight(19) = 0.385501531786156291289624969468E-01;
    weight(20) = 0.399537411327203413866569261283E-01;
    weight(21) = 0.412625632426235286101562974736E-01;
    weight(22) = 0.424735151236535890073397679088E-01;
    weight(23) = 0.435837245293234533768278609737E-01;
    weight(24) = 0.445905581637565630601347100309E-01;
    weight(25) = 0.454916279274181444797709969713E-01;
    weight(26) = 0.462847965813144172959532492323E-01;
    weight(27) = 0.469681828162100173253262857546E-01;
    weight(28) = 0.475401657148303086622822069442E-01;
    weight(29) = 0.479993885964583077281261798713E-01;
    weight(30) = 0.483447622348029571697695271580E-01;
    weight(31) = 0.485754674415034269347990667840E-01;
    weight(32) = 0.486909570091397203833653907347E-01;
    weight(33) = 0.486909570091397203833653907347E-01;
    weight(34) = 0.485754674415034269347990667840E-01;
    weight(35) = 0.483447622348029571697695271580E-01;
    weight(36) = 0.479993885964583077281261798713E-01;
    weight(37) = 0.475401657148303086622822069442E-01;
    weight(38) = 0.469681828162100173253262857546E-01;
    weight(39) = 0.462847965813144172959532492323E-01;
    weight(40) = 0.454916279274181444797709969713E-01;
    weight(41) = 0.445905581637565630601347100309E-01;
    weight(42) = 0.435837245293234533768278609737E-01;
    weight(43) = 0.424735151236535890073397679088E-01;
    weight(44) = 0.412625632426235286101562974736E-01;
    weight(45) = 0.399537411327203413866569261283E-01;
    weight(46) = 0.385501531786156291289624969468E-01;
    weight(47) = 0.370551285402400460404151018096E-01;
    weight(48) = 0.354722132568823838106931467152E-01;
    weight(49) = 0.338051618371416093915654821107E-01;
    weight(50) = 0.320579283548515535854675043479E-01;
    weight(51) = 0.302346570724024788679740598195E-01;
    weight(52) = 0.283396726142594832275113052002E-01;
    weight(53) = 0.263774697150546586716917926252E-01;
    weight(54) = 0.243527025687108733381775504091E-01;
    weight(55) = 0.222701738083832541592983303842E-01;
    weight(56) = 0.201348231535302093723403167285E-01;
    weight(57) = 0.179517157756973430850453020011E-01;
    weight(58) = 0.157260304760247193219659952975E-01;
    weight(59) = 0.134630478967186425980607666860E-01;
    weight(60) = 0.111681394601311288185904930192E-01;
    weight(61) = 0.884675982636394772303091465973E-02;
    weight(62) = 0.650445796897836285611736039998E-02;
    weight(63) = 0.414703326056246763528753572855E-02;
    weight(64) = 0.178328072169643294729607914497E-02;

  else

    fprintf ( 1, '\n' );
    fprintf ( 1, 'LEGENDRE_SET - Fatal error!' );
    fprintf ( 1, '  Illegal value of NORDER = %d\n', norder );
    fprintf ( 1, '  Legal values are 1 to 20, 32 or 64.\n' );
    error ( 'LEGENDRE_SET - Fatal error!' );

  end