[SOLVED - BUT!] Delivery Configuration for UK Only. Weight Ranges not working.

[DejaVu]

My site is almost ready to go live, but I cant seen

I've tried to setup my shop using the prices and weights from Royal Mail's Website (Packet 1st Class). Everything seems fine, but PrestaShop is not doing what it's supposed to.

Tried to attach images to the post to explain better, but wont let me. Attached direct links instead.

My Carrier (Which is Default)
http://i9.photobucket.com/albums/a88/DejaVuAtGesh/carrier.jpg

My 'Shipping Zones'
http://i9.photobucket.com/albums/a88/DejaVuAtGesh/shipping_zones.jpg

My Countries (United Kingdom set to United Kingdom Zone)
http://i9.photobucket.com/albums/a88/DejaVuAtGesh/coutries.jpg

Weight Ranges
http://i9.photobucket.com/albums/a88/DejaVuAtGesh/Weight_range_prices.jpg

Cart on adding something that's 0.1Kg's!
http://i9.photobucket.com/albums/a88/DejaVuAtGesh/cart.jpg


It's automatically defaulting to the Maximum amount for delivery @ 2-4Kg.
As soon as I can solve this, my site is ready to go live. Whoop!
Anyone able to shed any light? PLEASE!!

Is it perhaps too many Weight Variables?

[DejaVu]

Cant be sure, but I think I have sorted this and if I have it could be a bug.

I realised that the weight of my cart was exactly the same as a threshold of the Weight Range (0.1KG).
When I changed the Weight range slightly it worked fine.

Seems like, if the slightest chance the weight is the same as the threshold on the first item you add, it screws the calculation up.

I have no problem recreating this for someone else to evaluate my findings if someone's interested.

[SpyrosT]

This is not a bug. It just happens because you have gaps in your ranges.
when you are creating a new range you will see that
From: "weight" Range start (included)
To: "weight" Range end (excluded)

[DejaVu]

I see! That makes perfect sense now. LOL

Thanks SpyrosT

[SpyrosT]

You are welcome!
And remember that also the price ranges work the same way.

[taoreflex]

This is not a bug. It just happens because you have gaps in your ranges.
when you are creating a new range you will see that From: “weight” Range start (included) To: "weight" Range end (excluded)

Can anybody please clarify this. Looking at dejavu's weight ranges at the link he has provided I don't see any gaps. Each weight range starts exactly 1 gram above the previous weight range - 0kg - 0.1kg followed by 0.101kg - 0.25kg.

My weight ranges are the same. Does "gaps" mean that you actually have to have the weight ranges overlapping 0kg - 0.1kg and 0.1kg - 0.25kg? And if so which weight range does the overlapping weight actually fall into? The lower of the 2 weight ranges that its in or the higher of the 2?

[DejaVu]

There is a Gap.

0.1Kg - 0.101.kg Leaves a gap of 0.1005Kg

Just use -

0.1Kg - 0.2Kg
0.2Kg - 0.5Kg
Etc.

It does make sense. just a little difficult to explain.

It's all about the calculations. But Prestashop is designed to take for it.

Overlapping is the way to go.

[taoreflex]

You mean that Prestashop's weights work in increments of half a gram (0.0005 kg = half a gram). I presume you mean that 0.1005 exists in the space between 0.1 and 0.101. If you substract 0.1 from 0.101, you certainly don't get a gap of 0.1005. The gap between the two is 0.001. Probably means that one of the programmers is a member of the Foundation for the Implementation of Half Gram Increments in Postal Pricing. They don't seem to have got any takers amongst the world's post offices yet, but you have to admire them for persistence.

So if you overlap as you say, and for my first weight range I charge £1.00 and for the 2nd £1.50
0.1Kg – 0.2Kg - £1.00
0.2Kg – 0.5Kg - £1.50
into which weight category will 0.2kg fall. Will it get charged £1.00, or £1.50, or both - £2.50?

Whichever way it gets charged its going to do somebody's head in as you can't have one weight in 2 weight ranges without rewiring the brain to accept abnormal maths.

Presumably, it would work, without causing any brain damage, like this:
0.1kg - 0.2kg
0.2005kg - 0.5kg

Any Prestashop users who would like to support the work of the Foundation for the Implementation of Half Gram Increments in Postal Pricing can make a donation at their Prestashop website. Donations must end in a half (half a cent, half a euro cent, half a pence, etc).

[rocky]

It is 0.1kg included to 0.2kg excluded and 0.2kg included to 0.5kg excluded, so 0.2kg will match the second range, not the first range.

[taoreflex]

Thanks for the explanation Rocky.

Is there any chance of tracing the maths professor who taught the the programmer to do maths like that. They need to be shot (American way), sequestered for life (European way), or reprogrammed (Native American way). If this kind of maths gets around the space shuttle will no longer make it off the ground, satelite television viewers will suddenly find they're getting Channel XXX for free, and nobody will be able to work out how long to roast a beef joint for because they won't know what weight range it falls into.
Must have been a strange maths class. He/she must have counted, 0 to 1, 1 to 2, 2 to 3, in order not to have gaps.

On a more serious note, what does the customer see? Is it going to be responsible for frying customer's brains who think that they are going to be charged x amount for 0.2kg but will actually be charged more because 0.2kg actually falls into the next range. Or do customers not see any of this (possible kept from them as part of a massive global mathematical conspiracy)?

[rocky]

The shipping ranges aren't displayed to the customer, so they won't know how their shipping rate was calculated.

[taoreflex]

Thanks, now all is clear.

Though not sure whether to say pheeeew! or be alarmed by the cover up of what may well be a global mathematical conspiracy with consequences which we can only begin to imagine.

[taoreflex]

Even the wiki doesn't know about this use of "quantum reverse logic multi-overlap mathematics" (yes there is a name for this kind of maths). I found the instructions for setting up shipping in the wiki (see attached image) and there are no overlaps.

A huge battle is now expected to take place between supporters of the wiki writers (traditional maths) and supporters of the programmers (quantum reverse logic multi-overlap maths). Will the traditional mathematicians prevail and condemn us and Prestaship to life in a single dimension? Or will the multi-overlap mathematicians be allowed to open, for us and Prestashop, the doors of the quantum world and parallel universes? Watch this space for the latest developments in Herge's Adventures in Multi-Overlap Mathematics.

PS. for anyone still having problems understanding the concept of overlapping weight ranges, just think of it like a very tall club sandwich (the kind that only a hippopotamus could get its mouth around).

[SpyrosT]

The weight ranges shown in your attachment wont work perfectly. You still have gaps there.
Lets say you have a product of 1kg or 1.5kg or 2kg. These are not included as these
are the end of range which is "exluded".
This ranges will work ONLY if you never set any product at 0.5, 1, 1.5, 2 ect.

[rocky]

Well, consider me a "quantum reverse logic multi-overlap mathematician". I don't understand how the weight ranges in the screenshot could ever work. Under which range would 0.505kg fit? It would fit none of them, so having overlapping ranges makes sense.

[taoreflex]

Well, consider me a "quantum reverse logic multi-overlap mathematician". I don't understand how the weight ranges in the screenshot could ever work. Under which range would 0.505kg fit? It would fit none of them, so having overlapping ranges makes sense.

The screenshot is from the Prestahop wiki - the page that shows you how to set up shipping.

All that one needs to know to have been able to do this with traditional maths is the unit (smallest unit) that is being used. In quantum reverse logic multi-overlap mathematics you must have an infinite number of possible places after the decimal point, meaning that you would require overlap to cover all possibilites. In the table from Prestashop wiki you would have to infer that the smallest unit of measure is 10g (0.010kg). 0,505kg would therefore not be an option as 505g is not a multiple of 10g. This is not only an example of traditional maths at its finest, its also far more logical as you don't have an unexplained (until this thread finally wheedled out the answer) duplication of weights in 2 ranges.

Whats so extraordinary about quantum reverse logic multi-overlap mathematics is that it can be used as one's one and only reason for living, precisely because of its ability to go to infinity. So you might ask "Under which range would 0.505kg fit?" And a traditionalist will say, "Ahhh, OK, so I change it to 0.001kg to 0.500kg and 0.501kg - 1kg, then 0.505kg will fit in the second range. At which point you ask, "Under which range would 0.5005kg fit, etc, etc, etc. At which point you ask, "Under which range would 0.50005kg fit, etc, etc, etc. At which point you ask, "Under which range would 0.500005kg fit, etc, etc, etc.The quantum reverse logic multi-overlap mathematician will thus be able to keep this up as long as his computer can store enough zeros (after which he buys some chalk and starts writing 0s on the worlds motorways, freeways, etc). The traditional mathematician simply says, I'll set my unit of measure to 10g (covers virtually all postal and courier services) or 1g (if they're a stickler for accuracy, but don't want to get obsessive) and the whole problem of appearing to have weights appearing in two different weight ranges disappears. This is why you will see some 90 year olds running around in school playgrounds. These were quantum reverse logic multi-overlap mathematical schools. When asked to separate into groups according to age, in the quantum reverse logic multi-overlap mathematical schools, they were asked to form groups of 6-8 year olds and 8-11 year olds. Those 90 year olds still running around were 8 years old at the time, and are still trying to work out which group they should be in. In traditional schools they asked the pupils to separate into 6-8 year olds and 9-11 year olds. Not having been educated in quantum reverse logic multi-overlap mathematics, they all knew to which group they belonged.

[Canarias]

I'll have a problem with the shipping costs

 

Example :

A product weights 0.025 grams ( envelop )

I'll have 2 carriers

BPost and TNT Post

Bpost is for envelop and packages

TNT only for packages

BPost is for example for the Netherlands 3.09 euro for 0.0250 grams

TNT Post is is the weight from 0.350 grams

Under 0.350 grams is for BPost

But in the order cart the program gives the choice between 2 carriers

BPost 3.09 euro ( is correct )

TNT Post 9.99 euro ( is not correct )

I will that TNT Post not come visible in this case

In the shipping costs i'll have given 0.350 tot 10 kg

How is that possible please ?

Is there a solution ?

Thanks

[Dave L]

In your carriers set the Out of range behaviour to 'disable carrier'. Then if the shipping is not within the weight range of this carrier it will be disabled and not show on checkout.