function module - Page 104

Does the MySQLdb module support prepared statements ?

- by planetp

Does MySQLdb support server-side prepared statements? I can't figure this out from its manual.

Haskell Add Function Return to List Until Certain Length

I want to write a function which takes a list and constructs a subset of that list of a certain length based on the output of a function. If I were simply interested in the first 50 elements of the sorted list xs, then I would use fst (splitAt 50 (sort xs)). However, the problem is that elements in my list rely on other elements in the same list. If I choose element p, then I MUST also choose elements q and r, even if they are not in the first 50 elements of my list. I am using a function finderFunc which takes an element a from the list xs and returns a list with the element a and all of its required elements. finderFunc works fine. Now, the challenge is to write a function which builds a list whose total length is 50 based on multiple outputs of finderFunc. Here is my attempt at this: finish :: [a] -> [a] -> [a] --This is the base case, which adds nothing to the final list finish [] fs = [] --The function is recursive, so the fs variable is necessary so that finish -- can forward the incomplete list to itself. finish ps fs -- If the final list fs is too small, add elements to it | length fs < 50 && length (fs ++ newrs) <= 50 = fs ++ finish newps newrs -- If the length is met, then add nothing to the list and quit | length fs >= 50 = finish [] fs -- These guard statements are currently lacking, not the main problem | otherwise = finish [] fs where --Sort the candidate list sortedps = sort ps --(finderFunc a) returns a list of type [a] containing a and all the -- elements which are required to go with it. This is the interesting -- bit. rs is also a subset of the candidate list ps. rs = finderFunc (head sortedps) --Remove those elements which are already in the final list, because -- there can be overlap newrs = filter (`notElem` fs) rs --Remove the elements we will add to the list from the new list -- of candidates newps = filter (`notElem` rs) ps I realize that the above if statements will, in some cases, not give me a list of exactly 50 elements. This is not the main problem, right now. The problem is that my function finish does not work at all as I would expect it to. Not only does it produce duplicate elements in the output list, but it sometimes goes far above the total number of elements I want to have in the list. The way this is written, I usually call it with an empty list, such as: finish xs [], so that the list it builds on starts as an empty list.

Search Results

Search found 44058 results on 1763 pages for 'function module'.

Page 104/1763 | < Previous Page | 100 101 102 103 104 105 106 107 108 109 110 111 | Next Page >

- by planetp

- by kienjakenobi

- by AdmiralJonB

- by Patrick

- by marko

- by Yvon Blais

- by prince23

- by alzoid

- by Pedro

- by John Holecek

- by user637364

- by user211808

- by Nick Lowman

- by Juanjo Conti

- by b3y4z1d

- by checcco

- by ashish yadav

- by LoudNPossiblyRight

- by justintime

- by Valamas

- by m4recek

- by Space

- by WhyKiki

- by Scarface

- by user1816768

< Previous Page | 100 101 102 103 104 105 106 107 108 109 110 111 | Next Page >