Articles by Dave Britten

  1. Median-Median Regression For TI-86

    Despite being released about 4 years after the TI-82, the TI-86 does not include median-median regression, which can be a useful method of linear regression for data with extreme outliers. Fortunately it's a simple enough algorithm to implement in a small program.

    Tagged as : ti-86
  2. chmod Calculator For TI-86

    Here's a small TI-86 program for twiddling Linux/UNIX permission bits and seeing both the symbolic and numeric results. The simple ones (750, 640, 755, etc.) are easy enough to do in one's head, but it can start to get a bit messy when setuid, setgid, and sticky get involved.

    Tagged as : ti-86 linux unix
  3. Some Programs For the Casio fx-6300g

    I bought an old Casio fx-6300g graphing calculator from ebay (it's so tiny!), and couldn't find many programs written for it. Who would imagine that the internet wouldn't be awash in programs for an obscure, low-end calculator from 27 years ago? So, I wrote a few: prime factors, binomial probability, and negative binomial probability.

    Tagged as : casio calculator fx-6300G
  4. I Wish SQL Server Had FOREACH

    Know what would be awesome? If, instead of the usual cursor-and-local-variables ceremony, T-SQL would let you just do something like this:

    FOREACH logrow IN (SELECT logdate, logtime, event_type, user_name, result FROM LogData) FAST_FORWARD
    BEGIN
        INSERT INTO failure_log SELECT logrow.logdate, logrow.logtime, logrow.user_name WHERE logrow.result != 'SUCCESS'
    
        EXEC do_something_with_log_data @date = logrow.date, @time = logrow.time, @result = logrow.result
    END
    

    But alas, it does not. I'll have to continue to put up with a bunch of DECLAREs and 'FETCH NEXT INTO...'

    Tagged as : sql-server
  5. How To Center a div

    <table style="margin-left: auto; margin-right: auto">
        <tr>
            <td>
                <div>Yes, CSS and I have something of a love-hate relationship. How did you guess?</div>
            </td>
        </tr>
    </table>
    
    Tagged as : css lolz
  6. Pounding a New Nail With a 30-Year-Old Hammer

    Personal Information Management The Old Fashioned Way

    I have crohn's disease. It's not terminal or anything like that, but that's the most succinct way of conveying that I see a lot of doctors, and take a lot of medication. For a few years, I've hemmed and hawed over how to keep all of my records someplace organized. I've spent hours looking at database apps for my iPhone and iPad, I've considered using some version of MS Access (or a similar tool) to build my own, and I've looked at various hosted "cloud" solutions ...

    Tagged as : database retrocomputing
  7. Fiscal Year Functions for SQL Server

    These aren't particularly sophisticated, but we had a sudden need to do some reporting based on a vendor's fiscal year, and this should get the job done. Use freely (at your own risk).

    CREATE FUNCTION dbo.first_day_of_fiscal_year(@date datetime, @fiscal_year_start_month int, @fiscal_year_start_day int)
    RETURNS date
    AS
    BEGIN
        DECLARE @fy_start datetime = CAST(DATETIMEFROMPARTS(YEAR(@date), @fiscal_year_start_month, @fiscal_year_start_day, 0, 0, 0, 0) AS date)
        IF @fy_start > @date
            SET @fy_start = DATEADD(year, -1, @fy_start)
        RETURN @fy_start
    END
    
    GO
    
    CREATE FUNCTION dbo.last_day_of_fiscal_year(@date datetime, @fiscal_year_start_month int, @fiscal_year_start_day int)
    RETURNS date
    AS
    BEGIN
        RETURN DATEADD(dy, -1, DATEADD(year, 1, dbo.first_day_of_fiscal_year ...
    Tagged as : sql-server
  8. Linked Report Drill-Through With SQL Server Reporting Services

    We've got a fairly large Reporting Services installation in our organization. We've been using it for about eight or nine years, so we've accumulated several hundred reports in that time. Without going into undue detail about the server organization, we have all the deployed reports in a directory structure underneath "/Base Reports" that makes it easy for developers to see where (i.e. project, solution) a given report came from. All of these reports are then presented in separate directory structures where all the security is defined, e.g. a directory for the sales team, purchasing team ...

    Tagged as : ssrs sql-server