I am trying to create a signal and indicator that will calculate a trend line that can be used to create entry/exit signal. Does anyone have some sample code that I can take a look at for doing this? I want to create a line based on bottoms or tops of a trend channel. Here's a pic of what I'm looking to do...

https://photos.app.goo.gl/WYPEsjEvaQ2kzoMU7

I did one for Ninjatrader, you can look at the code though it is developed in Ninjascript which is an extention of the "C Sharp" language.

 

Code

/// indicator name : tiyfSlopeInterceptor /// *** Descrition *** /// Its mission is to move any selected Horizontal Line to the common point (x,y coordinate axes) between a Ray and the current bar. /// This indicator updates the y-location of any selected Horizontal Line /// to the common point (x,y coordinate axes) between a Ray and the current bar. /// /// How to use: /// 1- a Ray must be drawn anywhere on the chart. There can be many Rays on the chart but only one single Ray can be active. /// 2- A ray gets activated when the user simultaneously presses the left control key (left Ctrl) and clicks on the Ray. Doing this repeatedly will flip the state of the Ray between active/inactive. /// 3- Once the user selects an Horizontal Line, the line will start to follow the Ray (trend line) at the current bar as long as the h. line stays selected. /// 4- to detach the Horizontal Line from the Ray. The user can unselect the Horizontal Line or flip the state of the Ray to inactive.

The interesting part of the code is located in this method:
private LineCalculation calculate_YIntercept( string lineTagName )

See attached text file with extention .cs

OK, so I started experimenting and created the following indicator just to see if it will plot a trend line on a flexrenko chart. It would plot a trend line with the starting point being on bar number 165 at 4185.00 and the end point being at bar number 1051 at 4180.50.

It did successfully plot the line, but it taxed the hell out of my processor. And when I say taxing, I opened the task manager and the CPU usage for MC went from 0.1% to 9%. And I have a robust system. Do all plotting codes do this?



Vars:
TL_ID(0), StartBar(165), EndBar(1051), StartPrice(4185.00), EndPrice(4180.50);

TL_ID = TL_New_BN(StartBar, StartPrice, EndBar, EndPrice);
TL_SetExtRight(TL_ID, True);
TL_SetSize(TL_ID, 4);
TL_SetColor(TL_ID, Blue);

Sinatra Fan,

no, but your code "asks" for this. Think about what it does exactly and how many trendlines it potentially creates.

Regards,

ABCTG

Sinatra Fan 

OK, so I started experimenting and created the following indicator just to see if it will plot a trend line on a flexrenko chart. It would plot a trend line with the starting point being on bar number 165 at 4185.00 and the end point being at bar number 1051 at 4180.50. It did successfully plot the line, but it taxed the hell out of my processor. And when I say taxing, I opened the task manager and the CPU usage for MC went from 0.1% to 9%. And I have a robust system. Do all plotting codes do this? Vars: TL_ID(0), StartBar(165), EndBar(1051), StartPrice(4185.00), EndPrice(4180.50); TL_ID = TL_New_BN(StartBar, StartPrice, EndBar, EndPrice); TL_SetExtRight(TL_ID, True); TL_SetSize(TL_ID, 4); TL_SetColor(TL_ID, Blue);

ABCTG 

Sinatra Fan, no, but your code "asks" for this. Think about what it does exactly and how many trendlines it potentially creates. Regards, ABCTG

Not sure I understand. It plotted one line. Is there a more efficient approach to this. If so, I'm all ears. I'm a complete noob to coded trend lines. Thanks

Sinatra Fan,

I am not sure I understand what you mean by that. Are you saying you are just seeing one line or did you actually check the number of drawings for the chart (for example by looking at all drawings via -> Format Drawings)?

Regards,

ABCTG

Sinatra Fan 

Not sure I understand. It plotted one line. Is there a more efficient approach to this. If so, I'm all ears. I'm a complete noob to coded trend lines. Thanks

ABCTG 

Sinatra Fan, I am not sure I understand what you mean by that. Are you saying you are just seeing one line or did you actually check the number of drawings for the chart (for example by looking at all drawings via -> Format Drawings)? Regards, ABCTG

OK, so let me answer....

1) I only see 1 trend line.
2) I just checked and saw 499K drawings. This would obviously explain the draw on the CPU.

So, why is this happening and what can I do to stop this. Thanks

Sinatra Fan,

you need to keep in mind how your code is evaluated. It is called on every bar/tick and since you are drawing the trendline unconditionally, every call will result in a new trendline using the same values.
This is also the solution to you problem i.e. you will probably want to add a condition to ensure the trendline is only drawn once. What you use here is up to you.

Regards,

ABCTG

Sinatra Fan 

OK, so let me answer.... 1) I only see 1 trend line. 2) I just checked and saw 499K drawings. This would obviously explain the draw on the CPU. So, why is this happening and what can I do to stop this. Thanks

ABCTG 

Sinatra Fan, you need to keep in mind how your code is evaluated. It is called on every bar/tick and since you are drawing the trendline unconditionally, every call will result in a new trendline using the same values. This is also the solution to you problem i.e. you will probably want to add a condition to ensure the trendline is only drawn once. What you use here is up to you. Regards, ABCTG

So let's say I put a condition in there to calculate it once right at the point where the second (end) point is identified. What happens when I tell it to extend right? will it extend right even if it calculates one time?

I would suggest testing this. Any drawing attribute should remain as set until changed.

Sinatra Fan 

So let's say I put a condition in there to calculate it once right at the point where the second (end) point is identified. What happens when I tell it to extend right? will it extend right even if it calculates one time?