#### Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

New Members: Be sure to confirm your email address by clicking on the link that was sent to your email inbox. You will not be able to post messages until you click that link.

# Setting up a Bollinger Band + volume scan

Hi:
Could you please help me set up a scan using these 2 parameters:
1) Bollinger Band width is equal to or less than 6%; and
2) volume is above the 50-day average

• mod
edited March 2018
You can select and add all the items needed for your scan from the drop downs under the Scan Criteria window on the Advanced Scan workbench.

BB Width is under Technical Indicators.

Volume is under Price Volume and SCTRs

SMA is under Technical Indicators.

You will have to edit the default versions of each of these items to suit your needs.

If you haven't already, you will need get a handle on scan syntax. Start here:

Then go here:

https://stockcharts.com/docs/doku.php?id=scans:reference

This is a quick overview of the syntax rules:

Basic rules for the scan engine
Every statement begins with “and” or "or" except the first one. "or" is a special case. See below.
Every statement, except the word “and”, goes between square brackets [ ]
NOTE: Parentheses ( ) are reserved for indicators and functions, like RSI(14) or max(10,close). If you need to group arithmetic expressions, use more square brackets [ ], not parentheses: For instance:
And [ [high – close]/max(10, close) > 10]
Every statement contains an operator. Valid operator are: is, is not, >, <, =, !=, >=, <=, x, contains, not contains.” !=” means “not equal to”. “x” means “crosses above”.
Every statement has one value preceding the operator and one value after the operator.
Values can be indicators, overlays, numbers, reserved words like group, market cap, close, etc. (see drop downs on Advanced Scan page) or expressions using these values. Some examples:
[group is SP500] // note: this would be a first scan statement because it doesn’t begin with “and”
And [MACD Line(12,26,9] > 20]
And [MACD Line(12,26,9) x MACD Signal(12,26,9)]
You can also write “or” statements. “Or” statements need to be isolated with an extra set of brackets
// begin scan
[group is sp500]
// get bullish and bearish crossovers
And
[
[ MACD Signal (12,26,9) x 20]
Or
[ 80 x MACD Signal(12,26,9)]
]
// end scan
The double slashes "//" tell the scan engine to ignore everything on that same line that comes after the "//". So you can use that space to explain to yourself (for later) what you thought you were trying to do in the scan code.
NOTES on scan logic with “and” and “or”:
If a scan has ONLY “and” statements, all the “and” statements must be true for the scan to return a symbol.
If a scan has ONLY “or” statements, then only one condition must be true to return a symbol.
If a scan has a mix of “and” and “or” statements, the results depend on whether you isolated the “or” statement with extra brackets as shown above:
If you don’t use the brackets, then only one condition in the entire scan has to be true to return a symbol.
If you do use brackets, then every “and” condition must be true AND at least one “or” condition must be true to return a symbol.

Start simple. It's actually harder to figure out WHAT to code than HOW to code.

For instance, how would you code for a rising SMA 200?

You need to think about what would be true if the SMA 200 really is rising. First thought - the value today would be different from the value yesterday, or maybe 10 days ago or 100 days ago.
And it would be greater because it is rising. So the scan would compare today's SMA 200 to the past SMA 200 and it would be greater, so:

and [sma(200,close) > 10 days ago sma(200, close)]