请问在下面这个变成里面怎么设定坐标轴的尺度data one;
input x y;
datalines;
;
data fill;
do x=400 to 900 by 0.01; y=.; output; end;
run;
data one; set one fill; run;
proc sort data=one; by x;
proc nlin data=one;
parameters L=51 U=-0.09 R=600;
z1=(x<R)*(R-x);
model y = L + U*(z1);
output out=ppp p=predy;
run;
proc gplot;
title2 "2 linear broken lines" ;
goptions hpos=35 vpos=35 ftext=swiss;
symbol1 v=dot c=black;
symbol2 i=join v=none c=black;
plot y*x predy*x/overlay;
run;
