Simple tool that checks for missing bars and (too) big jumps between two consecutive bars.It will display for each symbol an error message whenever:- a bar is missing,- there's a big jump between two bars (close(i) / close(i-1) - 1 > MaxPercentage )- the close price of a bar is zero.How to use:- load the project- set the system params MaxPercentage and BarFrequency- set Data start date, end date and Frequency in the project properties pane- choose symbols in the "Symbol lists" pane- run project

The system can be downloaded by clicking here

For options quotes things get even weirder. I have found it necessary so far to check the following things real time:

• Bid = -1.
• Bid > 0, ask < bid, including ask = 0.
• ask=bid=0, which is 'normal' for an illiquid strike for awhile, but means these values are not actionable.
• (I anticipate spikes will be next.)

-Pete

See also Yahoo group about applying RE.

Here is a new version, that runs faster:

- set the system freq to daily, then perform all checks on a 1-min freq
- disable stats
- use Bars.maxlookback = 20