How to call a variable that is in qlikview into the another new variable in the js

[#1]

i want to get the value of the variable that is in qlikview into the variable that i have created in the js file or i want to assign the qlikview variable  to the variable in js

[#2]

You should have a look at this function: http://qlikcommunity.s3.amazonaws.com/misc/symbols/Qv.Document.html#GetAllVariables

[#3]

this url shows to get all variables but i want to get only a one variable which holds some numerical value can u give idea for that..... i am new to qlikview