Indicators - Bollinger Bands

bollinger_upper
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Usage: bollinger_upper(tradeValue, n, k)[-daysAgo]

returns the value for the upper bollinger band. This is calculated as a K times an N-period standard deviation above the middle band

Parameters:
tradeValue - the value for which the function is calculated, can be on of "open", "close", "high", "low" or "volume"
n - the number of days the functions is calculated for. If this is not specified a default value of 20 is used
k - value to multiply the standard deviation by. If this is not specified a default value of 2 id used
daysAgo - by default the calculations are done using the date specified in the filter definition, but optionally another parameter can be added to move the starting date a number of  days relative to the specified date


bollinger_lower
===============
Usage: bollinger_lower(tradeValue, n, k)[-daysAgo]

returns the value for the lower bollinger band. This is calculated as a K times an N-period standard deviation below the middle band

Parameters:
tradeValue - the value for which the function is calculated, can be on of "open", "close", "high", "low" or "volume"
n - the number of days the functions is calculated for. If this is not specified a default value of 20 is used
k - value to multiply the standard deviation by. If this is not specified a default value of 2 id used
daysAgo - by default the calculations are done using the date specified in the filter definition, but optionally another parameter can be added to move the starting date a number of  days relative to the specified date




bollinger_middle
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Usage: bollinger_middle(tradeValue, n)[-daysAgo]

returns the value for the middle bollinger band, which is calculated as a N-period simple moving average

Parameters:
tradeValue - the value for which the function is calculated, can be on of "open", "close", "high", "low" or "volume"
n - the number of days the functions is calculated for. If this is not specified a default value of 20 is used
daysAgo - by default the calculations are done using the date specified in the filter definition, but optionally another parameter can be added to move the starting date a number of  days relative to the specified date