Graphical gas price selection

[ngotchac]

Closes #2142

The description text might need to be edited...

[keorn]

Its not really octile since there are 9 sets. Is y axis the price for a particular quantile?

[jacogr]

It is based on what we get back from ethcore_gasPriceStatistics - but yes, it looks very scewed, we should adjust it somewhat so people go way below and way above as well.

[jacogr]

Think it is quite close, have a couple small nigglies I'll plop next to you for just in terms of layout.

Also want @gavofyork 's feedback on this one - he originally asked for it.
Probably @KenKappler as well...

[gavofyork]

@keorn and i always through you were good at maths! :-P

it's octile, because these are the quantiles which divide the distribution into 8 equal portions:

http://wikidiff.com/decile/octile

[gavofyork]

this is correct, fwiw (most people use sensible gas price, one or two people use 10x on that), though we may want to place Y on a log scale and/or remove max/min (first and last elements) from the graph.

[keorn]

Does 9 divisions make 8 sets (no, 7)? Not sure where that screenshot is from :P, here is a source.

[ngotchac]

Well, N+1 values makes N sets : [1, 2, 3] makes two sets: [1 ; 2] and [2 ; 3]

[keorn]

Yes, but quantiles divide the total population so only the internal divisions are meaningful. So does this mean that the graphic shows the most extreme values as the leftmost and rightmost bars?

[ngotchac]

Yes I think so.

So here are 3 different version, based on your comments:

1. Default version
   
2. Log scale
   
3. Sliced (without min and max)
   

[keorn]

3 looks about right (often 90% of transactions have the same price) and is not very nice. It might be better to have price on the x axis (where you do the sliding) and y axis would show the proportion of transactions you are ahead of.

[gavofyork]

the distribution is different to the original screenshot - all the bands are equal so it's rather dysfunctional. the data for the graph are indeed octile points, so the visualisation as bands is a little misleading. that said, 99% of users will not care at all.

[jacogr]

Moved to in-progress, different APIs for display to be added.

[ngotchac]

Current UI : https://youtu.be/0kINeUtmMJ8

[ngotchac]

Now using the new gasPriceHistogram RPC call : displays the gas price selection from this histogram.

[keorn]

As @rphmeier mentioned, might be good to say that these are included transactions. Also more outliers can be cut or more buckets used to make the histogram a bit more interesting, but the range now is usually between reasonable 20 and 50 Gwei.

[rphmeier]

(as a test, I submitted a tx yesterday with 15Gwei price. It took 12 hours to mine -- if you're comfortable with typical bank transfer times you might prefer the option to select outside of the range.)

[ngotchac]

The value can also be modified from the text input field on the right of the graph.

[coveralls]

Changes Unknown when pulling 1fdcf70 on ng-gas-price-selection into * on master*.

[jacogr]

We are entering the "this dialog is way too high" territory - cut 15% of the graph and combine the 2 paragraphs at the bottom. (It would make sense to do these 0.75em as well, just to fit in with "labelling")

Apart from that, looks almost usable now... We may want to try log scale again as well, just since there are massive jumps with the numbers.

[ngotchac]

So this is how it looks like with a log scale (far left is for 111 transactions, the second highest is 4 transactions)

As for the legend font size, 0.75em is really unreadable to me, so I put it at 0.9

[keorn]

imho
Can't this section be made optional (like advanced settings)? Default gas price from median is an alright estimator for most people who do not need to be shown all this complexity. Then you could have 3 steps + optional advanced settings.

[ngotchac]

@keorn Yep this is already the case. You have to check advanced settings (or equivalent) to access this gas price selector

[coveralls]

Changes Unknown when pulling 43dc939 on ng-gas-price-selection into * on master*.

[jacogr]

Lint issues, check GitLab/Travis.

[ngotchac]

Ok, fixed

[coveralls]

Changes Unknown when pulling 803543d on ng-gas-price-selection into * on master*.