octave:2> quad(@exp(x),0,1)
error: 'x' undefined near line 1 column 11
error: evaluating argument list element number 1
error: evaluating argument list element number 1
octave:2> quad(@(x) exp(x),0,1)
ans =  1.7183
octave:3> format long e
octave:4> integralgl(@(x) exp(x),0)
ans =    2.00000000000000e+00
octave:5> integralgl(@(x) exp(x),1)
ans =    2.34269608790973e+00
octave:6> integralgl(@(x) exp(x),2)
ans =    2.35033692868001e+00
octave:7> quad(@(x) exp(x),-1,1)
ans =    2.35040238728760e+00
octave:8> 
octave:8> integralgl(@(x) exp(x),3)
ans =    2.35040209215638e+00
octave:9> integralgl(@(x) exp(x),4)
ans =    1.78151349757394e+00
octave:10> integralgl(@(x) exp(x),4)
ans =    2.35040238646283e+00
octave:11> integralglab(@(x) exp(x),4,-1,-1)
error: 'integralglab' undefined near line 1 column 1
octave:11> ls
2017-10-16.txt	Bern.m	       gausssidel.m    integralgl.m~  r_jacobi.m
2017-11-06.txt	bezier.m       gausssidel.m~   jacobi.m       secanti2.m
2017-11-13.txt	broyden.m      gradott.m       jacobi.m~      secanti2.m~
2017-11-27.txt	broyden.m~     gradott.m~      newton.m       spline_notaknot.m
2017-12-18.txt	decasteljau.m  integralglab.m  newton.m~
2018-01-15.txt	gauss.m        integralgl.m    qr_shift.m
octave:12> integralglab(@(x) exp(x),4,-1,1)
error: 'integralglab' undefined near line 1 column 1
octave:12> diary off