600 setwidth 1.5 setformat -2.53 2.4 setxrange pictpointsOff /resolution 500 def %% echelle semi-ln /xscale { ln } def .08 11 setxrange -45 40 setyrange %% la legende $$ 20 {\rm log} \left| {1\over 1 + 2jm {\omega \over \omega _0} + \left( j {\omega \over \omega _0}\right)^2}\right| $$ .12 25 [1.2 dup] urtexlabel setSymbol (w/w) 8 -40 dctext (0) indice %% la numerotation /ymarkstyle {(-5 0) bltext} def .1 -40 setorigine [.1 .2 1 2 10] {xmark} apply 10 setymkstep ymarks 0 ymark .1 10 setxrange -40 40 setyrange masque gsave .4 setgray .4 setlinewidth %% les verticales [-1 1 log_seq] {svrule} apply %% les horizontales [-40 40 5 stepto] {shrule} apply grestore 1 setlinewidth %% la fonction a tracer /f { setxvar 1 0 1 0 0 x m mul 2 mul addc 0 x dupp mulc addc divc module log 20 mul } def /u {.5 0} def %% vecteur pour les traits de legende %% la courbe no 1 /m .01 def .1 1 {f} Courbe 1 xmax {f} Courbe %% et sa legende 1 dup f dupp point dupp u translatepoint /A defpoint A 1 trait $m = 0, 01$ A [1.2 dup] brtexlabel bleu %% la courbe no 2 /m .05 def {f} courbe 1 dup f dupp point dupp u translatepoint /A defpoint A 1 trait $m = 0, 05$ A [1.2 dup] brtexlabel orange %% la courbe no 3 /m .1 def {f} courbe 1 dup f dupp point dupp u translatepoint /A defpoint A 1 trait $m = 0, 1$ A [1.2 dup] brtexlabel noir %% la courbe no 4 /m .5 def {f} courbe 1 dup f dupp point dupp u translatepoint /A defpoint A 1 trait $m = 0, 5$ A [1.2 dup] brtexlabel /u {1.5 0} def bleu %% la courbe no 5 /m .707 def {f} courbe 1 dup f dupp point dupp u translatepoint /A defpoint A 1 trait $m = 0, 707$ A [1.2 dup] brtexlabel orange %% la courbe no 6 /m 1 def {f} courbe 1 dup f dupp point dupp u translatepoint /A defpoint A 1 trait $m = 1$ A [1.2 dup] brtexlabel /u {-.3 -10} def noir %% la courbe no 7 /m 2 def {f} courbe 1 dup f dupp point dupp u translatepoint /A defpoint A 1 trait $m = 2$ A [1.2 dup] dltexlabel bleu %% la courbe no 8 /m 5 def {f} courbe 1 dup f dupp point dupp u translatepoint /A defpoint A 1 trait $m = 5$ A [1.2 dup] dltexlabel