Using DSFunctions

Most indicators are a derivative of a core calculation.  For example, with Stochastic oscillators the raw %K statistic is the percentile of the close price within the range of a look-back period.  The %D statistic and the %Ds (slow stochastic) are but moving average derivations of the %K.  DS Functions (the DS stands for "Data Series") are a way to extend the derivations to get even for information.  In this exercise the velocity (i.e., the first order differential of price change) is calculated of the chart price series and then is used to derive acceleration (the second order differential of of price change).  An exponential moving average will be used as a surrogate of actual prices to help smooth the curves.

Step 1 - Select the input series

DS Functions create output data series from input series.  The input series may be another data series or a price series, though some functions such as the True Price Range) can only use price series as input.  In this example the chart price series will be the first input series.  Select the series by clicking on it in the price chart or selecting it in the Explorer pane (under Price Series in this case).  Notice that a series displays handles (small squares) when selected.

Step 2 - Insert the price series surrogate

In the Explore pane under DS Functions click on EMA.  In the Properties pane set the Periods property to 14 and press <enter>.  Now drag the EMA item onto the Price Chart.  The 14 period exponential moving average will be inserted into the Price Chart as shown in the example below.

Step 3 - Insert data series for "Velocity"

Create an empty indicator chart if one is not already available by selecting Insert / Chart from the menu.  While the EMA series is still selected, click on PRC (stands for Percent Rate of Change) from the DS Functions section of explorer.  Set the Period property to 10 and then drag the PRC indicator onto the blank chart.  The new series will be inserted into the chart.  While it is still selected, change the Name property of the series to "Velocity" as shown in the picture below.

Step 4 - Insert Acceleration

Finally. with the Velocity series selected, click on the ROC (Rate of Change) function, change its Period property to 10 and drag it onto the same chart as the Velocity series.  While the new series is still selected change its Name to "Acceleration", its Color to a light green and its GraphStyle to Histogram.  Reselect the Velocity series so that it plots over the top of the histogram.

The new series and their chart become permanent members of the current view.  To delete them select the chart by clicking on it (notice the chart's name will display in the status bar), then right-click and select Remove from the the pop-up menu.  Other options would be to Clear the chart, which removes the data series but retains the chart, or individually select the data series and Delete them with menu selections or by pressing the <delete> key.

Hints:
1)  You can reduce screen clutter by deleting the the original input and intermediate data series, the price EMA or Velocity in this case, and the derived series will still be retained because the input series' information is embedded in the formula of the derived series.
2)  Data series can be moved between charts by selecting them and dragging them to their new location while the <shift> key is depressed.  Multiple series can be selected by clicking them with the <control> key depressed.

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