Looks like I finally got this issue sorted.
After lots of experimenting, file hunting and tracing - and getting my maths brain into gear I made the changes below.
Files affected:
includes/classes/currencies.php
at the end of the file I changed
function display_price($products_price, $products_tax, $quantity = 1) {
return $this->format(zen_add_tax($products_price, $products_tax) * $quantity);
}
to this
function display_price($products_price, $products_tax, $quantity = 1) {
//-bof-frank18-Fix rounding error with tax calculation
return $this->format(zen_round(zen_add_tax($products_price, $products_tax), 2) * $quantity);
//-eof-frank18-Fix rounding error ...
}
includes/classes/order.php
changed (from around line 526)
/*********************************************
* Calculate taxes for this product
*********************************************/
$shown_price = (zen_add_tax($this->products[$index]['final_price'] * $this->products[$index]['qty'], $this->products[$index]['tax']))
+ zen_add_tax($this->products[$index]['onetime_charges'], $this->products[$index]['tax']);
$this->info['subtotal'] += $shown_price;
$this->notify('NOTIFIY_ORDER_CART_SUBTOTAL_CALCULATE', array('shown_price'=>$shown_price));
// find product's tax rate and description
$products_tax = $this->products[$index]['tax'];
$products_tax_description = $this->products[$index]['tax_description'];
to this
/*********************************************
* Calculate taxes for this product
*********************************************/
//$shown_price = (zen_add_tax($this->products[$index]['final_price'] * $this->products[$index]['qty'], $this->products[$index]['tax'])) // standard ZC1.5.1 code (frank18)
// next line is replacement which works a treat (frank18)
$shown_price = round((zen_add_tax($this->products[$index]['final_price'], $this->products[$index]['tax'])), 2) * $this->products[$index]['qty']
+ zen_add_tax($this->products[$index]['onetime_charges'], $this->products[$index]['tax']);
$this->info['subtotal'] += $shown_price;
$this->notify('NOTIFIY_ORDER_CART_SUBTOTAL_CALCULATE', array('shown_price'=>$shown_price));
// find product's tax rate and description
$products_tax = $this->products[$index]['tax'];
$products_tax_description = $this->products[$index]['tax_description']; // - shows correct product totals incl tax (frank18)
**includes/classes/shopping_cart.php
**
changed line 851
$this->total += zen_round(zen_add_tax($productTotal, $products_tax), $decimalPlaces) * $qty;
to this
// $this->total += zen_round(zen_add_tax($productTotal, $products_tax), $decimalPlaces) * $qty;
$this->total += zen_round(zen_add_tax($productTotal, $products_tax), 2) * $qty; // -frank18- correct rounding issue
Even though $decimalPlaces are set to '2' they won't take (don't know why???) - but by actually specifying 2 decimal places in that line fixed it
Finally in both of these files
includes/functions/functions_prices.php
admin/includes/functions/functions_prices.php
There are 5 instances in each of the 2 files showing
return number_format($blah_blah_variable, 4, '.', '');
which I all changed to
return number_format($blah_blah_variable, 2, '.', '');
I tested this on 3 different local ZC1.5.1 installs with normal priced products, products priced by attributes, products with special prices and products with sale maker prices. All are now showing fine on the shopping cart page, checkout_shipping, checkout_payment, checkout_confirmation and in admin - including the invoice. The fixes are now active on my main live store.
I would be grateful to see some comments on these changes - especially after seeing numerous reports on the same rounding issue on this forum and on the net - dating back to 2008.
If we are lucky, Ajeh (the shipping and payment module specialist :smile:) may take a look at this.
Cheers / Frank
