title: Pine Script beginner, plotshape
body: <p>Looking for a workaround, can't use plotshape in this way because it doesn't work in a local scope. </p>
  
  <pre><code>//@version=3
  study("MA test ", overlay=true)
  FastMA = sma(close, 9)
  SlowMA = sma(close, 15)
  Diff = FastMA - SlowMA
  if Diff &gt; 0
      plotshape(Diff, style=shape.arrowup, location=location.belowbar, color=green)
  </code></pre>