to me it seems that you are anyway relying on the assumption that the sequence is ordered, so I think it would be convenient to drop the "and"s
Gianluca On Sunday, February 16, 2014 11:31:46 PM UTC+1, Laurent Droin wrote: > > Hi, > > Disclaimer - I am completely new to Clojure. I just implemented my very > first (simple) program, letting me find out, from a GPX file, how much time > is spent in the various heart rate zones. Now that it's working, I'm > reviewing the code and trying to use best practices. From what I have read > so far, there are many ways in Clojure to do the same thing and for a > newbie, it's not always obvious to get a good grasp on what is the best way > to code a feature. > As a developer, and even though I love how concise Clojure programs can > be, I am very concerned with readability and ease of maintenance so I would > like to keep functions as short and tight as possible, but not to the point > where it becomes hard to understand what it does. > > Here is a function that I came up with that takes a bpm (heart beats per > minute) value, as well as a sequence of 4 values that represent the > boundaries defining the 5 different heart rate zones for a particular > person. > The function needs to finds out in what heart zone the bpm value falls > into and return that zone (as a keyword - I later use that keyword in a > map). > > If you're an experienced Clojure developer, what would you have done > differently (and why) ? > > *(defn hr-zone* > * "Return the HR zone as a keyword according to the bpm value."* > * [bpm [max-zone-1 max-zone-2 max-zone-3 max-zone-4]] * > * (cond * > * (<= bpm max-zone-1) :hr-zone-1* > * (and (< max-zone-1 bpm) (>= max-zone-2 bpm)) :hr-zone-2 * > * (and (< max-zone-2 bpm) (>= max-zone-3 bpm)) :hr-zone-3 * > * (and (< max-zone-3 bpm) (>= max-zone-4 bpm)) :hr-zone-4 * > * (< max-zone-4 bpm) :hr-zone-5))* > > FYI, here is how I call this function in the REPL: > (def my-hr-zones-defs [120 150 165 180]) > > (hr-zone 115 my-hr-zones-defs) > (hr-zone 133 my-hr-zones-defs) > (hr-zone 161 my-hr-zones-defs) > (hr-zone 175 my-hr-zones-defs) > (hr-zone 192 my-hr-zones-refs) > > Questions I have: > Would that make sense to consider (and maybe enforce) that the sequence > received as parameter is sorted? If this was the case, I would assume I > could avoid the "and" calls- assuming that all the conditions in the cone > form are evaluated in order. > Assuming that I need to test bpm against the two boundaries of each range, > would there be a better way to do this: > *(and (< max-zone-1 bpm) (>= max-zone-2 bpm))* > ? > Maybe this would work, but is it preferable? > *(< max-zone-1 bpm (dec **max-zone-2**))* > > *Thanks in advance for the advice.* > > *Laurent. * > > -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
