Re: How can I remove the nils in the result?
Colin, minor code review point that makes no real difference for this example but is a good habit to get into: try not to use last on vectors, use peek instead, otherwise it calls seq and steps through the entire sequence on each call. peek on the other hand does what you'd expect. For long lists this saves you a fair bit of work! On Wed, 24 Dec 2014 1:54 am Colin Jones wrote: > Thanks, I had fun with this! > > This isn't more concise, but I went in a little a different direction, > trying to pull the various concerns apart. In particular I had fun > separating: > - the idea of intervals for which any predicate passed from the specific > case of 0/1 equality comparison > - the string representation of intervals from their computation > - the idea of one-indexing from the rest of the problem > > https://gist.github.com/trptcolin/a573561ac9262092f254 > > - Colin > > p.s. There was no need for me to use `juxt` in `format-interval` but > honestly, if you're not going to use `juxt` at every conceivable > opportunity, why bother? > > > On Monday, December 22, 2014 10:09:06 PM UTC-6, Pauli wrote: >> >> Hi, all: >> >> I'm tring to solve such a problem: Given a string consisting of "1" and >> "0", find all the locations of "1", and print them in the format of >> intervals. >> >> For example: "00101110101110" => 3, 5-7, 9, 11-13 >> >> Here is my solution: >> >> (defn bar [x] >> (letfn [(foo [mystr] >> (->> >> (map-indexed vector mystr) >> (filter #(= (second %) \1)) >> (map (comp inc first)) >> (partition-all 2 1) >> (filter #(= 2 (count %)] >> (let [y (map #(if (> (- (second %) (first %)) 1) (print (first %) ", " >> (second %) "-")) (foo x))] >> (print (ffirst y) "-" y (last (last (foo x))) >> >> >> With the code above, I got many nils in the result: >> >> (bar "00101110101110") => 3 , 5 -nil - (nil nil 7 , 9 -nil 9 , 11 -nil >> nil nil nil) 13 >> >> How can I remove them? >> >> And, is there any way to make my code more concise? >> >> >> >> -- > 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/d/optout. > -- 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/d/optout.
Re: How can I remove the nils in the result?
Thanks, I had fun with this! This isn't more concise, but I went in a little a different direction, trying to pull the various concerns apart. In particular I had fun separating: - the idea of intervals for which any predicate passed from the specific case of 0/1 equality comparison - the string representation of intervals from their computation - the idea of one-indexing from the rest of the problem https://gist.github.com/trptcolin/a573561ac9262092f254 - Colin p.s. There was no need for me to use `juxt` in `format-interval` but honestly, if you're not going to use `juxt` at every conceivable opportunity, why bother? On Monday, December 22, 2014 10:09:06 PM UTC-6, Pauli wrote: > > Hi, all: > > I'm tring to solve such a problem: Given a string consisting of "1" and > "0", find all the locations of "1", and print them in the format of > intervals. > > For example: "00101110101110" => 3, 5-7, 9, 11-13 > > Here is my solution: > > (defn bar [x] > (letfn [(foo [mystr] > (->> > (map-indexed vector mystr) > (filter #(= (second %) \1)) > (map (comp inc first)) > (partition-all 2 1) > (filter #(= 2 (count %)] > (let [y (map #(if (> (- (second %) (first %)) 1) (print (first %) ", " > (second %) "-")) (foo x))] > (print (ffirst y) "-" y (last (last (foo x))) > > > With the code above, I got many nils in the result: > > (bar "00101110101110") => 3 , 5 -nil - (nil nil 7 , 9 -nil 9 , 11 -nil > nil nil nil) 13 > > How can I remove them? > > And, is there any way to make my code more concise? > > > > -- 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/d/optout.
Re: How can I remove the nils in the result?
whoops... (defn in-step [xs] (let [[x1 x2] xs] (= (- x2 x1) 1))) On Monday, December 22, 2014 11:38:49 PM UTC-8, Tim wrote: > > Another option (though Bens does look nicer!) > > (loop [xs (->> "00101110101110" > (map vector (iterate inc 1)) > (filter #(= (last %) \1)) > (map first)) > it nil] > (let [steps (partition 2 1 xs) > [i o] (split-with in-step steps)] > (cond (every? empty? steps) > (str it (first xs)) > (empty? i) > (recur (rest xs)(str it (first xs) ",")) >:else (recur (last (split-at (count i) xs)) (str it (ffirst i) "-") > > >> -- 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/d/optout.
Re: How can I remove the nils in the result?
Another option (though Bens does look nicer!) (loop [xs (->> "00101110101110" (map vector (iterate inc 1)) (filter #(= (last %) \1)) (map first)) it nil] (let [steps (partition 2 1 xs) [i o] (split-with in-step steps)] (cond (every? empty? steps) (str it (first xs)) (empty? i) (recur (rest xs)(str it (first xs) ",")) :else (recur (last (split-at (count i) xs)) (str it (ffirst i) "-") > -- 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/d/optout.
Re: How can I remove the nils in the result?
(it's also zero-indexed, unlike yours, but that isn't a big change) On Mon, Dec 22, 2014 at 9:17 PM, Ben Wolfson wrote: > This is a little more concise: > > (->> "00101110101110" >(map-indexed vector) >(partition-by second) >(filter #(= (second (first %)) \1)) >(map (comp (fn [[f & tail]] > (if rest (str f "-" (last tail)) (str f))) > (partial map first > > On Mon, Dec 22, 2014 at 8:09 PM, Pauli wrote: > >> Hi, all: >> >> I'm tring to solve such a problem: Given a string consisting of "1" and >> "0", find all the locations of "1", and print them in the format of >> intervals. >> >> For example: "00101110101110" => 3, 5-7, 9, 11-13 >> >> Here is my solution: >> >> (defn bar [x] >> (letfn [(foo [mystr] >> (->> >> (map-indexed vector mystr) >> (filter #(= (second %) \1)) >> (map (comp inc first)) >> (partition-all 2 1) >> (filter #(= 2 (count %)] >> (let [y (map #(if (> (- (second %) (first %)) 1) (print (first %) ", " >> (second %) "-")) (foo x))] >> (print (ffirst y) "-" y (last (last (foo x))) >> >> >> With the code above, I got many nils in the result: >> >> (bar "00101110101110") => 3 , 5 -nil - (nil nil 7 , 9 -nil 9 , 11 -nil >> nil nil nil) 13 >> >> How can I remove them? >> >> And, is there any way to make my code more concise? >> >> >> >> -- >> 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/d/optout. >> > > > > -- > Ben Wolfson > "Human kind has used its intelligence to vary the flavour of drinks, which > may be sweet, aromatic, fermented or spirit-based. ... Family and social > life also offer numerous other occasions to consume drinks for pleasure." > [Larousse, "Drink" entry] > > -- Ben Wolfson "Human kind has used its intelligence to vary the flavour of drinks, which may be sweet, aromatic, fermented or spirit-based. ... Family and social life also offer numerous other occasions to consume drinks for pleasure." [Larousse, "Drink" entry] -- 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/d/optout.
Re: How can I remove the nils in the result?
This is a little more concise: (->> "00101110101110" (map-indexed vector) (partition-by second) (filter #(= (second (first %)) \1)) (map (comp (fn [[f & tail]] (if rest (str f "-" (last tail)) (str f))) (partial map first On Mon, Dec 22, 2014 at 8:09 PM, Pauli wrote: > Hi, all: > > I'm tring to solve such a problem: Given a string consisting of "1" and > "0", find all the locations of "1", and print them in the format of > intervals. > > For example: "00101110101110" => 3, 5-7, 9, 11-13 > > Here is my solution: > > (defn bar [x] > (letfn [(foo [mystr] > (->> > (map-indexed vector mystr) > (filter #(= (second %) \1)) > (map (comp inc first)) > (partition-all 2 1) > (filter #(= 2 (count %)] > (let [y (map #(if (> (- (second %) (first %)) 1) (print (first %) ", " > (second %) "-")) (foo x))] > (print (ffirst y) "-" y (last (last (foo x))) > > > With the code above, I got many nils in the result: > > (bar "00101110101110") => 3 , 5 -nil - (nil nil 7 , 9 -nil 9 , 11 -nil > nil nil nil) 13 > > How can I remove them? > > And, is there any way to make my code more concise? > > > > -- > 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/d/optout. > -- Ben Wolfson "Human kind has used its intelligence to vary the flavour of drinks, which may be sweet, aromatic, fermented or spirit-based. ... Family and social life also offer numerous other occasions to consume drinks for pleasure." [Larousse, "Drink" entry] -- 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/d/optout.
How can I remove the nils in the result?
Hi, all: I'm tring to solve such a problem: Given a string consisting of "1" and "0", find all the locations of "1", and print them in the format of intervals. For example: "00101110101110" => 3, 5-7, 9, 11-13 Here is my solution: (defn bar [x] (letfn [(foo [mystr] (->> (map-indexed vector mystr) (filter #(= (second %) \1)) (map (comp inc first)) (partition-all 2 1) (filter #(= 2 (count %)] (let [y (map #(if (> (- (second %) (first %)) 1) (print (first %) ", " (second %) "-")) (foo x))] (print (ffirst y) "-" y (last (last (foo x))) With the code above, I got many nils in the result: (bar "00101110101110") => 3 , 5 -nil - (nil nil 7 , 9 -nil 9 , 11 -nil nil nil nil) 13 How can I remove them? And, is there any way to make my code more concise? -- 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/d/optout.
