DSP Robotics Support

Spogg wrote:I would like to see a method to prevent the counter itself going past set minimum and maximum values.

myvalue = [min_value, myvalue, max_value].sort[1]

RJHollins wrote:ah ... nice.

Interesting regarding the 'Clamp' concept.

I've been using something like this example. Restrict to values: 1 to 12

Code: Select all

s=[[12, x].min, 1].max

where x is Input values.

The SORT concept is something I need to play with/understand.

First question on it. What does the [1] identify ? [.sort[1]]

def clamp(x, min_value, max_value)
  if x < min_value
    return min_value
  elsif x > max_value
    return max_value
  else
    return x
end

result = clamp(3, 5, 20) #returns 5

tulamide wrote:

RJHollins wrote:ah ... nice.

Interesting regarding the 'Clamp' concept.

I've been using something like this example. Restrict to values: 1 to 12

Code: Select all

s=[[12, x].min, 1].max

where x is Input values.

The SORT concept is something I need to play with/understand.

First question on it. What does the [1] identify ? [.sort[1]]

Yes, using min and max is what I would call the common way. First get the smaller of x and max_value then get the larger of that and min_value. That's also, how I would prefer to do it in green.

Another way would be to work with conditionals.

Code: Select all

def clamp(x, min_value, max_value)
  if x < min_value
    return min_value
  elsif x > max_value
    return max_value
  else
    return x
end

result = clamp(3, 5, 20) #returns 5

The array sorting method however is so elegant and instinctively understandable. Layout is "left boundary, value, right boundary", which is easy to grasp. What happens is that an array is filled with these three values, then sorted and then the middle value from the array is returned [1] <- index starts at 0, so 1 is the second value.
If you use some numbers it becomes apparent:
[1, 5, 12].sort[1] -> after sort it's still [1, 5, 12] -> middle value is returned -> 5
[1, 0, 12].sort[1] -> after sort it's [0, 1, 12] -> middle value is returned -> 1
[1, 13, 12].sort[1] -> after sort it's [1, 12, 13] -> middle value is returned -> 12

HughBanton wrote:Next .. I wanted to try and revisit DaveyBoy's original purpose for this thread. Going right back to the very start, I can't get his original code to work properly. I get the 'watched' @clock OK - 0,1,0,1 etc, but I can only make isKeyPressed increment @selected if I substitute "shift" or "control" or "alt" keys; nothing at all happens with "up", "down", or for that matter any other key like "q" or "81" etc. (I haven't gone through many more ..)

Does it work OK for everyone else, or if you get what I get, is there an explanation?

Only problem so far is that it doesn't respond instantly as nine times out of ten the key will be pressed in between 'ticks'. (I don't want to use a fast clock to keep the CPU load down)

HughBanton wrote:Well, on my PC if I run it like this, substituting "shift" & "alt", it works (sort of) :

Code: Select all

ef init
   @clock = 0 
   @selected = 0
      input 100, nil
end

def event i,v,t      
   case i
   when 100
      input 100, nil, t + 0.25    
      @clock += 1
      @clock = 0 if @clock == 2
      if isKeyPressed "shift"
         @selected += 1            
      elsif isKeyPressed "alt"
         @selected -= 1
      end
      @selected = [0,@selected,10].sort[1]
   end
watch "@clock", @clock
watch "@selected", @selected   
end

.. but in its original form, with "up" & "down", I get no response at all. (Nor with their equivalents 38 & 40).

"q" & 81 are specifically quoted in the FS User Guide for isKeyPressed (page 202) but as I say I can only get very few of the keys on their list to work at all here, it's strange.

I expect DaveyBoy has long since moved on to something else, six months is a long time in Flowstone

I expect DaveyBoy has long since moved on to something else