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9709 :: A question about random returns

• Nanako (orginal) [2022-12-09T10:02:06+01:00] view original

  proc RandomImg(ctx: Context) {.async.} =

  let images = [

  1.jpeg", "2.jpeg", "3.jpeg", "4.jpeg", "5.jpeg", "6.jpeg" ]

  let pick = sample(images) doAssert pick in images resp "<img src='" & pick & "'/>"

  I'm using the random library to do a function that returns a random image but when I use randomize() and initRand(), it doesn't return a random result, it just returns a fixed result Is this a problem with my code?

  How do I use initRand() and randomize() correctly in this code?

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• pp (orginal) [2022-12-09T10:29:20+01:00] view original

  I guess you missed to call randomize

  
  #from https://nim-lang.org/docs/random.html
  import std/random
  # Call randomize() once to initialize the default random number generator.
  # If this is not called, the same results will occur every time these
  # examples are run.
  randomize()
  Run

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• pp (orginal) [2022-12-09T10:32:35+01:00] view original

  Sorry, reading better seems you did use randomize was at the beginning of the module?

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• Nanako (orginal) [2022-12-09T10:54:50+01:00] view original

  Using randomize() doesn't produce random results and I don't know what's wrong with it.

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• Clonk (orginal) [2022-12-09T11:07:02+01:00] view original

  Try formatting your code and posting a complete minimal reproducible example, otherwise it's hard to help you

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• pp (orginal) [2022-12-09T11:07:47+01:00] view original

  You can write your code into the playground at https://play.nim-lang.org/ than pasting the link generated we can check your code

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• foxoman (orginal) [2022-12-09T11:36:36+01:00] view original

  Not sure what you are using but here is an example using starlight

  import random
  import starlight
  
  randomize()
  
  var app = newApp(newSettings())
  
  proc hello(ctx: Context) {.async, get(app, "/hello").} =
    resp "Hello world!"
  
  proc randImg(ctx: Context) {.async, get(app, "randimg").} =
    
    let images = ["1.jpeg", "2.jpeg", "3.jpeg", "4.jpeg", "5.jpeg", "6.jpeg"]
    let pick = sample(images)
    echo pick
    resp "<img src='" & pick & "'/>"
  
  app.run()
  Run

  When opening http://127.0.0.1:8080/randimg

  it gives different result on every refresh with obvious repeating item :)

  
  DEBUG GET /randimg
  DEBUG 200 OK {"content-type": @["text/html; charset=UTF-8"]}
  DEBUG GET /2.jpeg
  DEBUG GET /randimg
  DEBUG 200 OK {"content-type": @["text/html; charset=UTF-8"]}
  DEBUG GET /3.jpeg
  DEBUG GET /randimg
  DEBUG 200 OK {"content-type": @["text/html; charset=UTF-8"]}
  DEBUG GET /3.jpeg
  DEBUG GET /randimg
  DEBUG 200 OK {"content-type": @["text/html; charset=UTF-8"]}
  DEBUG GET /5.jpeg
  DEBUG GET /randimg
  DEBUG 200 OK {"content-type": @["text/html; charset=UTF-8"]}
  DEBUG GET /3.jpeg
  DEBUG GET /randimg
  DEBUG 200 OK {"content-type": @["text/html; charset=UTF-8"]}
  DEBUG GET /3.jpeg
  Run

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