208 布林值出現買進訊號 問題

請問

這一個邏輯 "bbandwidth crosses above 5 "  意思是bbandwidth 由小變大超過0.05 ?

謝謝

//208 布林值出現買進訊號  
input:length(20);
variable:up1(0),down1(0),mid1(0),bbandwidth(0);
up1 = bollingerband(Close, Length, 1);
down1 = bollingerband(Close, Length, -1 );
mid1 = (up1 + down1) / 2;

bbandwidth = 100 * (up1 - down1) / mid1;
if bbandwidth crosses above 5 
and close > up1 
and close> up1[1] 
and average(close,20)>average(close,20)[1]  
then ret=1;