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Get a symbol's "low" price for today using data.history
Ben
posted Oct 8, 2018
Seeking Help

Hello there,

I'm struggling to compare today's low price with a propietary indicator line I'm generating (visually similar to a Bollinger Band lower band).

This is what I'm currently doing, which is not working.

I run a check of the status so I can trade at the market close: 

schedule_function(check_bands,date_rules.every_day(),time_rules.market_close())

I get the current price and the low price for today as follows:

 cur_price = data.current(context.stock,'price')  
 low_price = data.history(context.stock,'low',1,'1d')   #I'm not confident this is doing what i want

I calculate my indicator value and assign to the variable called: lower_band

I then compare today's low to the lower_band in order to generate trade signals:

if low_price[0] <= lower_band:  
#then go long

Problem is, I am not able to replicate the signals from my original (and trusted) excel prototype!

I suspect I am not getting today's low price in "low_price[0]"

Any hints /tips appreciated!

2 responses
Vladimir
Oct 8, 2018

Try this:

if low_price[-1] <= lower_band:

low_price_for_today = low_price[-1]

Ben
Oct 8, 2018

Tks Vladimir - When I ran both side by side (low_price[-1] & low_price[0]) and printed to screen, both produced the same values. I'm now trying to recreate in a notebook to understand more. If i learn anything useful I will post here. Tks again.

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