How can I set performance column value depends on SDI values?

I want to set performance column value depends on the values in SDI column in Interactive grid
I tried the following :

1- created page button and created dynamic action

2- I created the following java script code when click the button execute the code but its not working and not calculating the value this is the code :

var widget = apex.region('validate').widget();
var grid = widget.interactiveGrid('getViews','grid');
var model = grid.model;
var v_amount = 0; 

model.forEach(function (r) {

if (model.getValue( r , "SDI") >= 0 &&  model.getValue( r , "SDI") <= 1 ) 
{
    
      v_amount += 1
      model.setValue('PERF_ID',v_amount)
      //$s("PERF_ID",v_amount)
}
else if 
(model.getValue( r , "SDI") <= 0 &&  model.getValue( r , "SDI") >= -1 ) 
{
    
      v_amount += 1
      model.setValue('PERF_ID',v_amount)
      //$s("PERF_ID",v_amount)
}

else if 
(model.getValue( r , "SDI") >= 1.01 &&  model.getValue( r , "SDI") <= 1.5 ) 
{
    
      v_amount += 2
      model.setValue('PERF_ID',v_amount)
      //$s("PERF_ID",v_amount)
}

else if 
(model.getValue( r , "SDI") <= -1.01 &&  model.getValue( r , "SDI") >= -1.5 ) 
{
    
      v_amount += 2
      model.setValue('PERF_ID',v_amount)
      //$s("PERF_ID",v_amount)
}
else if 
(model.getValue( r , "SDI") >= 1.6 &&  model.getValue( r , "SDI") <= 2 ) 
{
    
      v_amount += 3
      model.setValue('PERF_ID',v_amount)
      //$s("PERF_ID",v_amount)
}
else if 
(model.getValue( r , "SDI") <= -1.6 &&  model.getValue( r , "SDI") >= -2 ) 
{
    
      v_amount += 3
      model.setValue('PERF_ID',v_amount)
      //$s("PERF_ID",v_amount)
}
else if 
(model.getValue( r , "SDI") > 2 ) 
{
    
      v_amount += 4
      model.setValue('PERF_ID',v_amount)
      //$s("PERF_ID",v_amount)
}

else if 
(model.getValue( r , "SDI") < -2 ) 
{
      v_amount += 4
      model.setValue('PERF_ID',v_amount)
      //$s("PERF_ID",v_amount)
}
})

enter image description here

see the image I need when click performance button calculate and set value in
performance column

PERF_ID and SDI is the columns name

Is the code java script syntax correct ?