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Message Removed
modified 11-Feb-18 3:32am.
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I'm getting an issue when I try to input data into a web page. However the issue is with my primary/foreign key in the database. Any help would be much appreciated.
Error message:
Error:System.Data.SqlClient.SqlException (0x80131904): The INSERT statement conflicted with the FOREIGN KEY constraint "UserIDfk". The conflict occurred in database "\\MAC\HOME\DOCUMENTS\COLLEGE\4TH YEAR\FYP\ITERATION 1\FYP-NEW\FYP-PARKWAY\FYP-PARKWAY\APP_DATA\USERDATA.MDF", table "dbo.Registration", column 'UserID'. The statement has been terminated. at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection, Action`1 wrapCloseInAction) at System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection, Action`1 wrapCloseInAction) at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj, Boolean callerHasConnectionLock, Boolean asyncClose) at System.Data.SqlClient.TdsParser.TryRun(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj, Boolean& dataReady) at System.Data.SqlClient.SqlCommand.FinishExecuteReader(SqlDataReader ds, RunBehavior runBehavior, String resetOptionsString, Boolean isInternal, Boolean forDescribeParameterEncryption) at System.Data.SqlClient.SqlCommand.RunExecuteReaderTds(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, Boolean async, Int32 timeout, Task& task, Boolean asyncWrite, Boolean inRetry, SqlDataReader ds, Boolean describeParameterEncryptionRequest) at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method, TaskCompletionSource`1 completion, Int32 timeout, Task& task, Boolean& usedCache, Boolean asyncWrite, Boolean inRetry) at System.Data.SqlClient.SqlCommand.InternalExecuteNonQuery(TaskCompletionSource`1 completion, String methodName, Boolean sendToPipe, Int32 timeout, Boolean& usedCache, Boolean asyncWrite, Boolean inRetry) at System.Data.SqlClient.SqlCommand.ExecuteNonQuery() at FYP_ParkWay.ListSpace.Button1_Click(Object sender, EventArgs e) in \\Mac\Home\Documents\College\4th Year\FYP\Iteration 1\FYP-NEW\FYP-ParkWay\FYP-ParkWay\ListSpace.aspx.cs:line 30 ClientConnectionId:dbdeb098-62a6-45bf-960b-374be8a4e13f Error Number:547,State: 0,Class:16
My primary key is:
CREATE TABLE [dbo].[Registration] (
[UserID] INT IDENTITY (1, 1) NOT NULL,
[Name] NCHAR (20) NULL,
[Surname] NCHAR (20) NULL,
[Email] NCHAR (30) NULL,
[Address] NCHAR (50) NULL,
[Phone] NVARCHAR (50) NULL,
[Password] NCHAR (30) NULL,
CONSTRAINT [pk_UserID] PRIMARY KEY CLUSTERED ([UserID] ASC)
)
The insert statement in which its referring is:
SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["RegistrationConnectionString"].ConnectionString);
conn.Open();
String insertQuery = "insert into ListSpace (Area,Date,StartTime,EndTime,Picture) values(@area, @date, @startTime, @endTime, @picture)";
SqlCommand com = new SqlCommand(insertQuery, conn);
com.Parameters.AddWithValue("@area", ddlArea.Text);
com.Parameters.AddWithValue("@date", cdrDate.SelectedDate);
com.Parameters.AddWithValue("@startTime", ddlStart.Text);
com.Parameters.AddWithValue("@endTime", ddlEnd.Text);
com.Parameters.AddWithValue("@picture", updPicture.FileBytes);
com.ExecuteNonQuery();
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Based on the error message you're trying to insert a row that tries to refer to a non-existent row in registration.
Ensure that you're adding the rows in correct order. For example add the row in registration table before adding any rows referring to that table.
One way to find the constraint definition and the table that caused the error is to use following query which shows the table and columns for the violated foreign key constraint.
SELECT *
FROM INFORMATION_SCHEMA.CONSTRAINT_COLUMN_USAGE ccu
WHERE ccu.CONSTRAINT_NAME = 'UserIDfk'
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I have 5 randomly generated numbers type in text field every time I press a button:
Something like this: 0.5670.9870.3420.5210.07 etc......They represent sensor values in range 0-1V
I would like to split them so that I get something like this:
0.567 0.987 0.342 0.521 0.07
Also I would like to add a line shift so that every time I press the button the number series goes onto next line.
Anybody has an idea ?
This is my main Form1.cs class:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace DAQ_Simulator
{
public partial class Form1 : Form
{
int counter;
private DateTime datetime;
private DateTime datetime2;
int maxAI = 7;
int maxDI=3;
int maxSid =10;
string sTxt;
string sTxt1;
Sensor[] sObj = new Sensor[10];
public Form1()
{
InitializeComponent();
for (counter = 0; counter < maxSid; counter++)
{
sObj[counter] = new Sensor(counter);
}
}
private void displaySensorData(object sender, EventArgs e)
{
}
private void groupSampl_Enter(object sender, EventArgs e)
{
}
private void textSampling_TextChanged(object sender, EventArgs e)
{
}
private void btnSampling_Click(object sender, EventArgs e)
{
timer1.Interval = 5900;
timer1.Start();
btnSampling.Enabled = false;
sampling();
if (textSampling.Text == "")
{
textSampling.Text = "Sample";
}
datetime2 = DateTime.Now.AddSeconds(5).AddMilliseconds(900);
string time2 = datetime2.Hour + ":" + datetime2.Minute + ":" + datetime2.Second + "." + datetime2.Millisecond;
textSampling.Text =time2;
System.TimeSpan diff1 = datetime2.Subtract(datetime);
}
private void groupLogg_Enter(object sender, EventArgs e)
{
}
private void txtLogging_TextChanged(object sender, EventArgs e)
{
}
private void labelLoggingText_Click(object sender, EventArgs e)
{
}
private void btnLogging_Click(object sender, EventArgs e)
{
}
private void labelSensorValues_Click(object sender, EventArgs e)
{
}
private void textSensorValues_TextChanged(object sender, EventArgs e)
{
}
private void timer1_Tick(object sender, EventArgs e)
{
btnSampling.Enabled = true;
timer1.Stop();
}
private void sampling()
{
datetime = DateTime.Now;
string time = datetime.Hour + ":" + datetime.Minute + ":" + datetime.Second + "." + datetime.Millisecond;
for (counter = 0; counter < maxAI; counter++)
{
sTxt += sObj[7].GetAnalogValue().ToString("F3");
}
for (counter = 0; counter < maxDI; counter++)
{
sTxt1 += sObj[3].GetDigitalValue().ToString();
}
textSensorValues.Text = time + "\r\n" + sTxt+sTxt1;
}
}
}
This is my Sensor.cs class:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace DAQ_Simulator
{
public class Sensor
{
double dVal;
int DigVal;
int sId;
Random rSensVal;
public Sensor(int id)
{
sId = id;
rSensVal = new Random(id);
dVal = 0.0F;
}
public double GetAnalogValue()
{
dVal = rSensVal.NextDouble();
return dVal;
}
public double GetDigitalValue()
{
Random ranDigVal = new Random();
DigVal= ranDigVal.Next(0,2);
return DigVal;
}
public int GetSensId()
{
return sId;
}
}
}
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Hi,
rather than struggling with a problem you created yourself (see the line with sTxt+=...getAnalogValue...) you should try and avoid the problem from the start.
I have several ideas:
- don’t concatenate numbers in a string without a separator; by adding a space or some symbol (say #) you could ease the string splitting later on (have a look at the string.Split method!)
- much better yet, don’t confuse your “business logic” with your user interface, i.e. store your measurement results one by one in an appropriate data structure (could be a List<float> or so), and do whatever is required for displaying separately.
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I apologize if my questions seem "stupid".
Back to this problem, I managed to "solve" the problem but I don't think the solution is good even though it works when I run the program.
The instructor of this class I am taking told us to use for loops to solve this problem of getting sensor values and ID numbers of the sensors. I did not do that.
I get completely lost when I need to create an array for sensor values and match it with sensor IDs.
Another thing I am struggling with is how to compare dates. I have a time stamp that indicates clock-time for every sample. A sample time is 5,seconds which means I have to disable Sample button for 5,seconds after clicking it. I used Date.Time.Now and tried to compare dates, I basically have to times one that is current and other that is 5,9 seconds ahead., but since both clocks are running I am not able to apply if/else statement to compare them.
Would you please take a look at this code and let me know if there is any nicer way of solving this preferably with loops.
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace DAQ_Simulator
{
public partial class Form1 : Form
{
int counter;
private DateTime datetime;
private DateTime datetime2;
int maxAI = 7;
int maxDI=3;
int maxSid =11;
Sensor[] sObj = new Sensor[11];
public Form1()
{
InitializeComponent();
for (counter = 0; counter < maxSid; counter++)
{
sObj[counter] = new Sensor(counter);
}
}
private void displaySensorData(object sender, EventArgs e)
{
}
private void groupSampl_Enter(object sender, EventArgs e)
{
}
private void textSampling_TextChanged(object sender, EventArgs e)
{
}
private void btnSampling_Click(object sender, EventArgs e)
{
timer1.Interval = 5900;
timer1.Start();
btnSampling.Enabled = false;
sampling();
datetime2 = DateTime.Now.AddSeconds(5).AddMilliseconds(900);
string time2 = datetime2.Hour + ":" + datetime2.Minute + ":" + datetime2.Second + "." + datetime2.Millisecond;
textSampling.Text =time2;
}
private void groupLogg_Enter(object sender, EventArgs e)
{
}
private void txtLogging_TextChanged(object sender, EventArgs e)
{
}
private void labelLoggingText_Click(object sender, EventArgs e)
{
}
private void btnLogging_Click(object sender, EventArgs e)
{
}
private void labelSensorValues_Click(object sender, EventArgs e)
{
}
private void textSensorValues_TextChanged(object sender, EventArgs e)
{
}
private void timer1_Tick(object sender, EventArgs e)
{
btnSampling.Enabled = true;
timer1.Stop();
}
private void sampling()
{
datetime = DateTime.Now;
string time = datetime.Hour + ":" + datetime.Minute + ":" + datetime.Second + "." + datetime.Millisecond;
double sensVal1 = sObj[1].GetAnalogValue();
double sensVal2 = sObj[2].GetAnalogValue();
double sensVal3 = sObj[3].GetAnalogValue();
double sensVal4 = sObj[4].GetAnalogValue();
double sensVal5 = sObj[5].GetAnalogValue();
double sensVal6 = sObj[6].GetAnalogValue();
double sensVal7 = sObj[7].GetAnalogValue();
int sensVal8 = sObj[8].GetDigitalValue();
int sensVal9 = sObj[9].GetDigitalValue();
int sensVal10 = sObj[10].GetDigitalValue();
String analogSens1 = sensVal1.ToString("F3");
String analogSens2 = sensVal2.ToString("F3");
String analogSens3= sensVal3.ToString("F3");
String analogSens4 = sensVal4.ToString("F3");
String analogSens5 = sensVal5.ToString("F3");
String analogSens6 = sensVal6.ToString("F3");
String analogSens7 = sensVal7.ToString("F3");
String digSens8 = sensVal8.ToString("F0");
String digSens9 = sensVal9.ToString("F0");
String digSens10 = sensVal10.ToString("F0");
textSensorValues.Text += (" " + time + " " + analogSens1 + " " + analogSens2+ " " + analogSens3 + " " + analogSens4+
" "+ analogSens5+" "+analogSens6+" "+ analogSens7+" "+digSens8+" "+digSens9+" "+digSens10+"\r\n");
}
}
}
Sensor class:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace DAQ_Simulator
{
public class Sensor
{
Random ranDigVal;
double AnalogVal;
int DigVal;
int sId;
Random rSensVal;
public Sensor(int id)
{
sId = id;
rSensVal = new Random(id);
ranDigVal = new Random(id);
AnalogVal = 0.0F;
}
public double GetAnalogValue(double minAnalogVolt=0.00F,double maxAnalogVolt=1.00F)
{
if(minAnalogVolt <= AnalogVal && AnalogVal<= maxAnalogVolt)
AnalogVal = rSensVal.NextDouble();
return AnalogVal;
}
public int GetDigitalValue(int digMin = 0, int digMax = 1)
{
DigVal = ranDigVal.Next(0, 2);
return DigVal;
}
public int GetSensId()
{
return sId;
}
}
}
modified 10-Feb-18 14:09pm.
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Hi,
I have lots of comments, here are just a few:
1. I don't think Sensor.GetAnalogValue() is doing what you think it is doing, I fail to see how the current code could be useful. Maybe you should first add a comment explaining what the method is supposed to do, and only then compare the code with the written description.
2. I see two new Random() statements inside Sensor. They tell me you did not understand the matter that was handled in your earlier thread, two days ago.
This is what the Random class does:
- each NextValue() returns a value assumed to be random, however it is never random, it is pseudo-random, which means anyone knowing the internal code can predict the next value. The values returned are from a huge but fixed and circular list (not stored but calculated), and the only random thing about it is you can influence where in the list the sequence will start, that is what the "seed" does.
- If you provide the same seed to different Random instances, you get the same values returned.
- And if you don't, the .NET Random class will derive a seed from the current time with millisecond resolution. As creating a Random object takes much less than a millisecond, two consecutive new Random() will typically use the same seed.
Normally, the easy way to correctly use Random is by having only one of them, so make it a static field within your Sensor class.
3. If you already know what Properties are, you shouldn't have a method called GetSensId(). If properties still are in your future, then don't bother for now.
4. Having a lot of variables with almost identical names (sensVal#, analogSens#) in general indicates bad design; you should consider avoiding so many variables in the first place, and when you really need them all at the same time, then consider an aggregate, such as an Array. Doing so your code will turn out to be more concise, clearer, and less prone to typing errors.
5. A method that is intended to obtain some values, such as sampling(), normally should make those values available to the other methods and properties of the class; yours doesn't, it has type void, and the only thing coming out of it is a complex string going to the screen. There are many ways to provide values, the obvious one is by using a return statement (you could return an Array of floats, of a List of doubles, or whatever suits you); alternatives are "out" parameters (don't abuse those!), and in some cases class-level variables (not recommended here). I hope you notice how this fits well with the previous comment.
6. You should not export information through a GUI element (such as a TextBox), except towards the program user; a program that shows information to the user in one part of the code, and then tries to regain that information from the GUI is extremely bad design. You should rely on data structures, what the user sees should be an afterthought, and not an essential part of operation.
7. Over time you will learn to carefully choose identifier names; GetAnalogValue() is good, sampling() is not.
Keep learning!
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Why are you converting numbers to strings and then concatenating them all into an unparsable list? The only time you need to convert them to strings is when displaying or printing. Inside your application you should keep them as doubles at all times.
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I need to model multivariate polynomials where the number of variables depends on user input. I found it natural to model univariate polynomials as arrays of numbers representing the coefficients, whose indices represent the degrees of the terms they correspond to. The obvious extension to n-variable polynomials is an n-dimensional array, the index of an entry with respect to a given dimension representing the degree of the term with respect to a given one of the variables. However, it seems like it would be tricky to declare and manipulate such an object - I can't type int[][]...[] (n sets of brackets), after all. Alternatively, I could given up on the idea of encoding term degree in the positions of entries in the data structure, perhaps using a dictionary where the values are the coefficients and the keys are one-dimensional, n-element arrays specifying the degree of the term, but this approach would mean it would be necessary to do a bunch of searches every time the polynomial is operated on, which seems inelegant. Are there any other approaches I should consider?
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I've come up with an n-dimension array class:
class ndArray
{
int Dimensions;
int DimensionLength;
int[] Array;
public ndArray(int dimensions, int dimensionLength)
{
Dimensions = dimensions;
DimensionLength = dimensionLength;
int arrayLength = 1;
for (int i = 0; i < dimensions; ++i)
arrayLength *= dimensionLength;
Array = new int[arrayLength];
}
int getIndex(params int[] indices)
{
int index = 0;
int nsPlace = 1;
for (int i = 0; i < Dimensions; ++i)
{
index += indices[i] * nsPlace;
nsPlace *= DimensionLength;
}
return index;
}
public int getElement(params int[] indices)
{
return Array[getIndex(indices)];
}
public void setElement(int element, params int[] indices)
{
Array[getIndex(indices)] = element;
}
}
I'll have to see how this works in the context of polynomials. Maybe the static limit on dimension length will be a problem.
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Frequency of spreading what?
This space for rent
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\\
How can I create a program that shows information on DVB-T2 USB and shows it in a noutbook ???
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That makes no sense at all. About the best you're going to get for an answer is to consult the documentation and manufacturer support for the device you're trying to use.
If you have to ask "How do I write an entire application?", you're not going to get an answer for that question. It's a very generic question and impossible to answer with any accuracy at all.
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How do I link sliders together? Or trackbars.
I want to have 3 sliders set up so they are linked. So one slide bar can have 1 million and then as I use the other sliders that number will go down as the numbers go up in the other sliders.
Also, how do I get a slider to show the number above where my slider is? So if the slider is on 1 million it shows the text above my cursor as 1,000,000 and if I move it down the number decreases as I move the slider down.
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What have you tried? Where are you stuck?
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Step one is to get a slider control and see what properties and events it exposes. Then go from there.
Everyone is born right handed. Only the strongest overcome it.
Fight for left-handed rights and hand equality.
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This is easy to do with TrackBar Controls in WinForms, but, first, you have to precisely define what "linkage" is: do the TrackBars have independent value ranges, or, over-lapping ranges ?
If changing one TrackBar's value can change the other TrackBars' values, you'll need to prevent recursion.
Need a "read-out:" position a Label over the TrackBar and use that, or use a ToolTip.
Clarify your goal, and show some code.
«... thank the gods that they have made you superior to those events which they have not placed within your own control, rendered you accountable for that only which is within you own control For what, then, have they made you responsible? For that which is alone in your own power—a right use of things as they appear.» Discourses of Epictetus Book I:12
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I want one track bar to hold the total of the other track bars. So if the total is 100 the track bars added together can't add up to greater than 100.
Track bars set out like say:
10
20
50
20
Total 100
Or
30
10
30
30
Total 100
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Okay, this a good first step in specifying behavior.
The next step is to define the minimum and maximum range for each trackbar; of course, you can change this at run-time with code.Member 13670442 wrote: one track bar to hold the total of the other track bars
Are you saying that this trackbar sets the maximum value of the total of values of the other trackbars ? If so, how would changing its values affect the current values of the other trackbars ?
«... thank the gods that they have made you superior to those events which they have not placed within your own control, rendered you accountable for that only which is within you own control For what, then, have they made you responsible? For that which is alone in your own power—a right use of things as they appear.» Discourses of Epictetus Book I:12
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Yes. The other track bars would be limited by the Total track bar. If the Total track bar is 100 all the track bars must add up to that track bar and no more. If I were to move the Total track bar down the other track bars move down too. Until they react zero.
50
10
10
10
10
Total 90
10
0
0
0
10
Total 20
If having the Total track bar isn't possible I could do it without a Total tack bar. I just need the code that will link multiple track bars together.
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I'm trying to write an algorithm in C#, this algorithm includes so many transfer function in laplace space, such as 2nd order high-pass or low-pass filters, integrals and derivatives, I converted all of them into discrete form, but I don't know how to add them to my C# code. for example how can I implement this transfer function in C# code:
H(z)= 4/(2z+3)
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Maybe I'm missing something, but isn't your example just:
public double H(double z)
{
return 4.0 / ( 2.0 * z + 3.0);
}
Bad command or file name. Bad, bad command! Sit! Stay! Staaaay...
AntiTwitter: @DalekDave is now a follower!
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I am making a DAQ-Simulator that shall simulate generation of analog (0-1V) and digital 1 or 0 signals.
When I call my method sampling () and display the sensor data in my textbox, I always get the same numbers for my Analog sensors. Since this is a Random generation it should have been different numbers every time I click on Sample button 
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
<pre lang="c#">namespace DAQ_Simulator
{
public partial class Form1 : Form
{
int counter;
int maxSid = 10;
int maxAI, maxDI;
string sTxt;
private DateTime datetime;
Sensor[] sObj = new Sensor[10];
public Form1()
{
InitializeComponent();
}
private void displaySensorData(object sender, EventArgs e)
{
}
private void groupSampl_Enter(object sender, EventArgs e)
{
}
private void textSampling_TextChanged(object sender, EventArgs e)
{
}
private void btnSampling_Click(object sender, EventArgs e)
{
sampling();
}
private void groupLogg_Enter(object sender, EventArgs e)
{
}
private void txtLogging_TextChanged(object sender, EventArgs e)
{
}
private void labelLoggingText_Click(object sender, EventArgs e)
{
}
private void btnLogging_Click(object sender, EventArgs e)
{
}
private void labelSensorValues_Click(object sender, EventArgs e)
{
}
private void textSensorValues_TextChanged(object sender, EventArgs e)
{
}
private void timer1_Tick(object sender, EventArgs e)
{
}
private void sampling()
{
for (counter = 0; counter < maxSid; counter++)
{
sObj[counter] = new Sensor(counter);
}
for (counter = 0; counter < maxSid; counter++)
{
for (counter = 0; counter < 10; counter++)
{
sObj[counter] = new Sensor(counter);
}
for (counter = 0; counter < maxSid; counter++)
{
sTxt += sObj[counter].GetAnalogValue().ToString("F3");
textSensorValues.Text = sTxt;
}
textSensorValues.Text=sTxt;
}
}
}
}
This is my Sensor class where I call the GetAnalogValue() from:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace DAQ_Simulator
{
public class Sensor
{
double dVal;
bool bVal;
int sId;
Random rSensVal;
public Sensor(int id)
{
sId = id;
rSensVal = new Random(id);
dVal = 0.0F;
}
public double GetAnalogValue()
{
dVal += rSensVal.NextDouble();
return dVal;
}
public int GetDigitalValue()
{
Random bVal = new Random(2);
int digital = bVal.Next(2);
return digital;
}
public int GetSensId()
{
return sId;
}
modified 8-Feb-18 12:54pm.
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You're specifying the same seed each time, so you'll get the same sequence of pseudo-random numbers each time.
You can generate the same sequence of random numbers by providing the same seed value to the Random(Int32) constructor.
"These people looked deep within my soul and assigned me a number based on the order in which I joined."
- Homer
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