Calculate Standard Deviation for the given data points
Below code will give us the Standard Deviation for the list data (double type) provided.
You need to be carefully in handle 'Divide by zero' error.
Formulae for the Standard Deviation:
standard deviation
Code here :
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 | /// <summary> /// Return the Standard Deviation for the provide set of data array to the calling function. /// Parameter : Double Array /// </summary> public static double StandardDeviation(double[] data) { double ret = 0; double DataAverage = 0; double TotalVariance = 0; int Max = 0; try { Max = data.Length; if (Max == 0) { return ret; } DataAverage = Average(data); for (int i = 0; i < Max; i++) { TotalVariance += Math.Pow(data[i] - DataAverage, 2); } ret = Math.Sqrt(SafeDivide(TotalVariance, Max)); } catch (Exception) { throw; } return ret; } private static double Average(double[] data) { double ret = 0; double DataTotal = 0; try { for (int i = 0; i < data.Length; i++) { DataTotal += data[i]; } return SafeDivide(DataTotal, data.Length); } catch (Exception) { throw; } return ret; } private static double SafeDivide(double value1, double value2) { double ret = 0; try { if ((value1 == 0) || (value2 == 0)) { return ret; } ret = value1 / value2;</code> } catch { } return ret; } |
How to create a event in MySQL (Schedule to run a Store procedure)
Below statement will set an event on MySQL Database which will be fired at a given interval. You could execute another query or call a Stored Procedure to accomplish you daily routine tasks.
CREATE EVENT 'Event Name'
ON SCHEDULE EVERY 1 DAY -- 'Day Interval'
STARTS '2009-06-29 13:05:' -- 'Start time - Execute on the same time every day'
DO CALL 'Stored Procedure with Parameter;
How to send mail using smtpclient
You can create a Mail Message dynamically and send the mail to recepient list through smtp client. You need to use System.Net.Mail to use the smtp client class.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 | using System.Configuration; using System.Net.Mail; public static bool SendMailNotification() { MailMessage msg = new MailMessage(); try { StringBuilder strBody = new StringBuilder(""); strBody.Append("<span style='font-size: 9pt; font-family: Arial'>" + team + " Message body goes here<b>" + DateTime.Now.ToString("MMMM") + "</b><br /> "); strBody.Append("<br/><span style='font-size: 16pt; font-family: Arial'>Message body goes here<b>" + "</b></span><br /> <br />"); string[] lsMailList = "Get mail receiptent list from database"; foreach (string mail in lsMailList) { msg.To.Add(mail); } msg.From = new MailAddress("from@domain.com"); msg.Subject = "any Subject to the mail"; AlternateView Body = AlternateView.CreateAlternateViewFromString(strBody.ToString(), null, "text/html"); msg.AlternateViews.Add(Body); SendMail(msg); return true; } catch (Exception ex) { return false; } } public static void SendMail(MailMessage msg) { try { SmtpClient smtp = new SmtpClient(); smtp.Host = ConfigurationSettings.AppSettings["MailServer"].ToString(); //relay server name smtp.Send(msg); } catch { } } |
Below is a MySql trigger to insert/update other table
Trigger in backend is very useful to report the input data in many different way.. This will be last step in performance tuning when the data double up drastically.
DROP trigger IF EXISTS "Trigger Name";
delimiter $$
CREATE TRIGGER "Trigger Name"
AFTER INSERT ON "Table Name - where the trigger will be fired on Insert/Update"
FOR EACH ROW
BEGIN
Declare l_count, l_topErrorCount INT;
Declare l_Top1Error, l_Top2Error, l_Top3Error VARCHAR(150);
//To determine where you need to update or insert the value in other table
SELECT COUNT(*) INTO l_topErrorCount FROM "Table Name"
WHERE Team = NEW.Team
AND Date = NEW.ErrorDate
AND Report = NEW.Report;
////
You Logic goes here.....
//Retrive Top Error...//
////
IF l_topErrorCount > 0 THEN
UPDATE "Table Name"
SET Top1Error= l_Top1Error,
Top2Error=l_Top2Error,
Top3Error=l_Top3Error
WHERE Team = NEW.Team
AND Date = NEW.ErrorDate
AND Report = NEW.Report;
ELSE
INSERT INTO "Table Name"
(Date, Team, Report, Top1Error, Top2Error, Top3Error)
VALUES(NEW.ErrorDate, NEW.Team, NEW.Report, l_Top1Error, l_Top2Error, l_Top3Error);
END IF;
END;
$$
How to Write bunch of text to a file
Here is one of the way to Write bunch of text to flat file:
1 2 3 4 5 6 7 8 9 10 11 12 | Public Sub WriteFile(ByVal sText As String, ByVal sFile As String, Optional ByVal bAppendMode As Boolean = True) Try Dim Stream_Writer As New IO.StreamWriter(sFile, bAppendMode) Stream_Writer.Write(sText & vbCrLf) Stream_Writer.Flush() Stream_Writer.Close() Catch ex As Exception 'Statements to handle Errors Finally End Try End Sub |