主题：sum函数算不出结果来

variable:sumwealth=0;
ma10:ma(c,10);
ma25:ma(c,25);
sxf:=0.01/100;//手续费0.01%
hh:holding,linethick0;
if holding>0 and ma10<ma25 then begin
 sell(1,1,thisclose);
 sumwealth:=sumwealth+1*c*300*(1-sxf);//卖出时减去交易额
end
if holding<0 and ma10>ma25 then begin
 sellshort(1,1,thisclose);
 sumwealth:=sumwealth-1*c*300*(1+sxf);//买入时加上交易额
end
if holding=0 and ma10>ma25 then begin
 buy(1,1,thisclose);
 sumwealth:=sumwealth-1*c*300*(1+sxf);
end
if holding=0 and ma10<ma25 then begin
 buyshort(1,1,thisclose);
 sumwealth:=sumwealth+1*c*300*(1-sxf);
end

ib:todaybar,linethick0;

zichan:sumwealth+holding*c*300-abs(holding)*c*300*sxf,noaxis;
zch1:zichan-ref(zichan,ib),linethick0;
mryl:ifelse(todaybar=ref(todaybar,todaybar),zch1,0),linethick0;

5ryl: sum(mryl,555),linethick0;

黑体的这行为什么计算不出结果来呢？哪里错了？谢谢