equation


    Jun 22 2011 | 11:13 am
    hi
    i try to make the equation on the pict.
    corresponding to Multiply the x coordinate of each vertex by the y coordinate of the next vertex.
    like this : ($1 * $4) + ($3 * $6) + ($5 * $8) + ($7 * $10) + ($9 * $12)
    if anyone can help me ! thanks f

    • Jun 22 2011 | 11:17 am
      This seems to a perfect task for [expr].
    • Jun 22 2011 | 11:57 am
      yes sure.... but if i write it on the form : ($i1 * $i4) + ($i3 * $i6) + ($i5 * $i8) + ($i7 * $i10) + ($i9 * $i12) expr don't work, be in black and max window say $ symbol variable out of range... i don't know what kind of operators used or is it necessary to used several expr ?
      thanks f
    • Jun 22 2011 | 12:05 pm
      like this is ok but maybe tyey are a most effective way ?
      thanks f
    • Jun 22 2011 | 12:12 pm
      cant' see your patch here. but the error message is because [expr] takes only up to nine arguments. so you could split the tasks into two expressions or maybe do it in Javascript using a single [js].
    • Jun 22 2011 | 12:21 pm
      ok
      thanks f
    • Jun 22 2011 | 12:59 pm
      split it up.
      if it is a list, use something like zl iter 2 or zl iter 4, then write an an expr.
    • Jun 22 2011 | 10:33 pm
      Throw some iteration in there and do the maths:
    • Jun 23 2011 | 11:03 am
      hi
      thanks Luke, this run good and seems me the most efficiently, and can run with different size of list...
      all the best f
    • Jun 23 2011 | 10:09 pm
      Not a problem, scalability is always good. This way you can change the list length and the offset, happy to help!