Gravity.efs
EFSLibrary - Discussion Board
File Name: Gravity.efs
Description:
The Center Of Gravity
Formula Parameters:
- Length : 10
Notes:
This indicator identifies every major turning point without much lag.
This indicator is computed in a similiar way to the Ehlers filter.
The position of the balance point is the summation of the product of position within the observation window multiplied by the price at that position divided by the summation of prices across the window. The formula is:
CG = SUM(x+1) * Price(i) / SUMPrice(i)
In this formula "1" is added to the position count because it starts with the most recent price at zero, and multiplying the most recent price by that position count would remove it from the computation.
Download File:
Gravity.efs
EFS Code:
/********************************* Provided By: eSignal (Copyright c eSignal), a division of Interactive Data Corporation. 2009. All rights reserved. This sample eSignal Formula Script (EFS) is for educational purposes only and may be modified and saved under a new file name. eSignal is not responsible for the functionality once modified. eSignal reserves the right to modify and overwrite this EFS file with each new release. Description: The Center Of Gravity Version: 1.0 05/05/2009 Formula Parameters: Default: Length 10 Notes: This indicator identifies every major turning point without much lag. This indicator is computed in a similiar way to the Ehlers filter. The position of the balance point is the summation of the product of position within the observation window multiplied by the price at that position divided by the summation of prices across the window. The formula is: CG = SUM(x+1) * Price(i) / SUMPrice(i) In this formula "1" is added to the position count because it starts with the most recent price at zero, and multiplying the most recent price by that position count would remove it from the computation. **********************************/ var fpArray = new Array(); var bInit = false; function preMain() { setStudyTitle("Center of Gravity Oscillator"); setCursorLabelName("Gravity", 0); setCursorLabelName("Temp", 1); setPriceStudy(false); setDefaultBarFgColor(Color.red, 1); setDefaultBarFgColor(Color.blue, 0); var x = 0; fpArray[x] = new FunctionParameter("Length", FunctionParameter.NUMBER); with(fpArray[x++]) { setLowerLimit(1); setDefault(10); } } var xGravity = null; function main(Length) { var nBarState = getBarState(); var nGravity = 0; var nTemp = 0; if (nBarState == BARSTATE_ALLBARS) { if(Length == null) Length = 10; } if (bInit == false) { xGravity = efsInternal("Calc_Gravity", Length); bInit = true; } nGravity = xGravity.getValue(0); nTemp = xGravity.getValue(-1); if (nTemp == null) return; return new Array(nGravity, nTemp); } var bSecondInit = false; var xHL2 = null; function Calc_Gravity(Length) { var nRes = 0; var i = 0; var nHL2 = 0; var num = 0; var denom = 0; if (bSecondInit == false) { xHL2 = hl2(); bSecondInit = true; } if (xHL2.getValue(-Length) == null) return; for(i = 0; i < Length; i++) { nHL2 = xHL2.getValue(-i); num += (1 + i) * nHL2; denom += nHL2; } if(denom != 0) nRes = - num / denom; return nRes; }