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Strange price history in debugger?


I see baffling behavior of prices from history for SPY

If I ask for 4 bars I see this in my debugger:

myts: TimeSeries
0_2014-10-20 20:00:00+00:00: 190.32
1_2014-10-21 20:00:00+00:00: 194.05
2_2014-10-22 20:00:00+00:00: 192.71
3_2014-10-23 13:31:00+00:00: 194.05

If I ask for 9 bars I see this:

myts: TimeSeries
0_2014-10-13 20:00:00+00:00: 187.38
1_2014-10-14 20:00:00+00:00: 187.75
2_2014-10-15 20:00:00+00:00: 186.29
3_2014-10-16 20:00:00+00:00: 187.75
4_2014-10-17 20:00:00+00:00: 187.38
5_2014-10-20 20:00:00+00:00: 187.75
6_2014-10-21 20:00:00+00:00: 186.29
7_2014-10-22 20:00:00+00:00: 187.75
8_2014-10-23 13:31:00+00:00: 187.38

When I print() the prices and inspect them in logs,
I see prices which match prices from yahoo-spy-history,
which is good.

This might be a bug.

Does Quantopian collect end-user bug reports at github? jira? e-mail?


Clone Algorithm
Total Returns
Max Drawdown
Benchmark Returns
Returns 1 Month 3 Month 6 Month 12 Month
Alpha 1 Month 3 Month 6 Month 12 Month
Beta 1 Month 3 Month 6 Month 12 Month
Sharpe 1 Month 3 Month 6 Month 12 Month
Sortino 1 Month 3 Month 6 Month 12 Month
Volatility 1 Month 3 Month 6 Month 12 Month
Max Drawdown 1 Month 3 Month 6 Month 12 Month
def initialize(context):
  context.spy = symbol('SPY')

def handle_data(context, data):
  prices = history(bar_count=4, frequency='1d', field='price')
  myts = prices[context.spy]
There was a runtime error.
3 responses

Hi Dan,

The values in the debugger aren't right yet: debugger problem
Joe gives a workaround of

from collections import OrderedDict  
OrderedDict(zip(myts.index, myts.values))  

Joe can you also trim() the debugger input -- adding whitespace before or after a debug command produces an error message:

SyntaxError: invalid syntax (<unknown>, line 1)  

Thanks for the comment about the leading and trailing whitespace. Fixes for these issues should be coming shortly.


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The SyntaxError part of that for leading or trailing whitespace with debugger commands would appear to be fine now.