sid-kap

Tried to make yogurt using skim milk and some starter that I made from probiotics. Fermented it in a yogurt maker for about 11 hours, and it turned out like this.

What am I doing wrong? Is there too much fermentation, or not enough?

Long-distance air travel emits extremely high amounts of greenhouse gases. (For people who fly between continents, their flights are often the largest component of their yearly carbon footprint.) Are there any realistic low-carbon alternatives (such as high-speed rail, boat, etc.) to commercial airlines for intercontinental trips that don't take too much (subjective, I know) longer than flying? Also, for same-continent trips, how much of emissions could be avoided by building high-speed rail and encouraging people to use that over flying (likely through carbon taxes)?

The City is in the process of introducing a new zoning code. (For those who don't know, the zoning code is the document that decides what kinds of buildings can be built where. This includes use (single-family, multifamily residential, retail, mixed-use), building height, parking requirements, etc.)

They have released a new draft code, which lists the new zones and their requirements, and a new draft map, which says which zones will be used on each plot of land. For West Campus, the map is not actually correct; there is actually something called the UNO (University Neig

Has there been any discussion about maybe adding a true hierarchical module structure, like Java/Scala, to PureScript, in place of the current Haskell-style modules, where dots in a module name don't have any semantic meaning?

On the one hand, this might make some things more convenient. For example, I could use Data.Char.isAlpha without any imports. Also, if I import Data, then I only need to do Char.isAlpha.

On the other hand, I could see some downsides:

• I think this might complicate finding the typeclasses in scope? i.e., if I use Data.Char.isAlpha somewhere, should the typeclasses in Data.Char automatically be brought into scope? (My first guess is that no, typeclasses s

At 22:03 in this talk, Evan talks about the "diamond problem" in concurrent programming.

He explained that, contrary to what you might expect, the following code does not return a stream of all true values:

diamond : Stream Float -> Stream Bool
diamond stream = 
  merge
    (==)
    (map sqrt stream)
    (map sqrt stream)

I don't understand why this would cause problems. Can someone explain this example to me?

If so, why or why not?

I'm working on a project that involves making web requests to a JSON API and parsing the result into Haskell types. In this project, I have a lot of code of the sort

data MyException = MyException String
instance Exception MyException where
  ...

data Thingy = Thingy { ... fields ... }

thingyParser :: String -> (Value -> Parser Thingy) -> Thingy
thingyParser = ...

getThingy :: IO Thingy
getThingy = do
  response <- Wreq.get "url"
  case Aeson.decodeEither (response ^. responseBody) of
    Left err   -> throwIO (MyException err)
    Right json ->
      case Aeson.parseEither myParser "Thingy parser" json of
        

For a school assignment, I'm working on a visualization of Dijikstra's algorithm and several variants of A* search.

I tried to mimic the imperative-style implementation of Dijiksta's found in most textbooks, so I wrote the algorithm in the ST monad and used mutable hashtables and heaps.

Unfortunately, I'm not happy with how the code reads. Unlike in other imperative languages, I feel like the only way to make this algorithm concise is by turning my code into operator soup, with lots of >>=, <*>, and <$>s.

(For example, the following code:

loopCondition = do
  heapNotNull <- not . PQueue.null <$> ST.readSTRef heap
  tNotVisited <- isN

I would love to see a canonical Haskell plotting library that rivals R, ggplot, and pyplot in features and extensibility.

I'm sure many people in the subreddit have used plotting tools in other languages, and wished there was a good Haskell tool for this purpose.

Furthermore, I think Haskell has many things going for it that should make it a good choice for a plotting library.

So, I have two questions:

1. Why don't we have a great plotting library? What stands in the way of making one?
2. For people familiar with Chart, does this seem like a good start toward the eventual goal? What could be improved about Chart? (One idea that I had, given the