How To Solve An Equation That Is A String
Feb 9, 2011I have an equation in the form of a string:
Dim Answer as Integer
Dim AnswerBox as New RichTextBox
'... Settings for AnswerBox
[code].....
I have an equation in the form of a string:
Dim Answer as Integer
Dim AnswerBox as New RichTextBox
'... Settings for AnswerBox
[code].....
Let's say I wrote 1+1 in a text box1 how to get answer in a text box2?
View 10 RepliesSo im making a program to solve second grage equations,its already working but i want to make it better,heres my idea.Right now the user must input the three equation coefficients (in a equation like 2x+2x+2 they are 2,2 and 2),i want to make it possible for them just to insert the equation like 2x+2x+2 and the computer will get that data,and extract the coefficients from it. [code]
View 1 RepliesI would like to read a user's input equation or expression as a string (such as "y=5*(x+6)" or "cos(3)^2") and have the program evaluate it mathematically. Does .Net have any classes that could do this? Obviously, the compiler can already take a programmer's coded equation and evaluate it. Of course this is a different matter, but is there not a way to harness that same power with runtime user-created equations? Serialization or anything?
The other option (I guess) would be to create my own equation-generator - breaking an equation down into a binary tree of the numerical values and the operations I suppose. Aside from being a nontrivial task, my program needs optimal performance as these equations are in large loops. At the very least, this would add several conditional evaluations to each equation run - dunno if that adds up.
. I get this error: "Cannot convert lambda expression to type 'string' because it is not a delegate type" - keyword select become underlined in blue
[Code]...
Above code should displays drop list of employees first name and last name in a combo box
how .net solve Dll problem??
View 1 RepliesThis is my matrix. I want to solve C,D and E
sample codes to solve C, D and E in VB.Net?
Answers are C=0.4857143, D=0.0000000 and E=-0.1428571 (manual calculation)
I have this home work question and I don't know what I am doing wrong there are a lot of errors which I don't know how to correct. This the question:An automative service shop performs the following services (all the services below are assigned a value):
Oil Change
Lube Job
Radiator flush
Transmision flush inspection
Muffler replacement and
Tire rotation
Create an application that displays the total for a customer's visit. This is my code so far:
[Code]...
I have single-thread windows form application written with VB.NET and targeting Framework 1.1. The software communicates with external boards through a serial interface, and it mainly consist of a state machine that run some tests, driven in a loop done with a Timer and an Interval of 50ms. The feedback on the user interface is done through some custom events raised during the tests.
The problem that is driving me crazy is that the performance slightly decrease over time, and in particular after 1200/1300 test operations. The memory occupied does not increase over time, it is only the CPU that seems interested by this problem. The strange thing is that, targeting framework 2.0 and using the same identical code, I do not have this problem.
I know that is difficult without looking at the code, but do you have suggestions how can I approach the problem? EDIT: I am really lost, after a couple of intensive work the application starts slowing down. The selected row is related to its process, if it could help.
EDIT2: Using the Windows Task Manager I detected that the Handles counter is increased by 1 at the end of each operation. I don't know if it is the cause but the application starts to slow down when the handles counter reaches about 1500 handles. I checked that all necessary RemoveHandler are called after each operation. Any idea?
EDIT3: I found that the handles problem is generated by the C++ library we are using to communicated with the serial device. It then happens both in .NET 1.1 and .NET 2.0. The difference, and that's strange, is that if the target .NET 1.1 the application slow down/freeze instead for .NET 2.0 I reached more than 30000 handles without loosing performances. Now I don't know if the problem is really caused by this lost handles, I will try to ask to the developers of C++ library to correct the problem and see if it solves the problem I am having on .NET 1.1.
I am trying to combine 2 regular expressions into 1 with the OR operator: |
I have one that checks for match of a letter followed by 8 digits:
Regex.IsMatch(s, "^[A-Z]d{8}$")
I have another that checks for simply 9 digits:
Regex.IsMatch(s, "^d{9}$")
[Code]...
Apparently I am not combining the two correctly and apparently I am horrible at regular expressions.And for those wondering, I did take a glance at How to combine 2 conditions and more in regex and I am still scratching my head.
I am using window 7, when I run my code in local everything is alright, but when upload to window server 2003 the code will coming error "String was not recognized as a valid DateTime".My computer setting (date format) all same with my window server.[code]
View 3 RepliesIn first search, result will show.In second search, the result in first searching will also show with the result in second searching. [code]
View 4 RepliesI am taken DateTimePicker2, DateTimePicker3 n textbox6.Now i wanted to display the result of subtraction of these two dates(DateTimePicker2-DateTime Picker3) in textbox6 automatically. I don't want to enter the result manually. Plz hlp me I need it badly. I hav already tried in lost focus event also its nt workin.
View 6 RepliesI have a lengthy query..always it shows timeout..I am filling it in a dataset, not using command execute.Is there anyway to solve this rather than optimizing the code? any way to solve the timeout..
View 3 RepliesSimilar to using VAL(a$) to return the numerical value of a string, is there a function for returning the solution of an equation that is user-typed into a textbox? For instance, user types F$=(a+b*x)/(c*x^2-d*x^3) where the variables of the equation are either pulled from a textbox or derived within the code. I am looking for something like F=Solve(F$).
View 5 RepliesI get an Operator not defined error at "SetAttr(j = fo.GetFolder("C:\Documents and Settings\a19238\My Documents\VB Grille OrderTest\"))"
[code]...
i'm going to create event application where's times like:
a) 17:00
b) 18:00
c) 20:00
(Current compuer's time: 17:16)How do i make my application detect timezone and change a), b) and c) times for the same timezone, that people knows if event is my time 17:00 so what it is in their time?
insert sql statement in array (vb 2005), or any other ways to solve it??
View 1 RepliesThe port connection is successful but when it gets to receive data I get this timeout exception. Got no idea what to do...what to fix
System.TimeoutException: The operation has timed out.
at System.IO.Ports.SerialStream.Read(Byte[] array, Int32 offset, Int32 count, Int32 timeout)
[code].....
I need a VB.NET program to solve linear system with any number of equations
View 5 RepliesI want to iterate through an equation and modify a number e.g. Multiply it by 10, where there is one. How do I do this?
View 4 RepliesI wanted to read input equation by user A+B and assign input user value to A and B to ask them to add and give answer. But I just can't get the code to work. I using VS2005 and VB.Net.[code]
View 1 RepliesCan I use a function for more than one equation?
Program Description: Fortuitous Dice is a game that requires two dice be rolled, one at a time. If p and q are the numbers rolled on the first and second die, respectively the value of the roll in the game is determined as follows:
P Q Rule (value of the roll and condition)
Even Odd 2P + Q
Odd Even P + 2Q
Even Even P + Q When P not = Q
P When P = Q
odd Odd P + Q When P not = Q
3Q When P = Q
i am having the Visual basic code which is following..
View 3 RepliesI have a decent understanding of the logic, the content. I'm working on a puzzle and I'd like to write a short program. I'm looking to fill in the following variables: AB.CDE FG.HIJ (they're part of coordinates, and the puzzle is part of a geocache)
The puzzle asks you to determine which numbers correspond to certain colors, like this:
[code...]
I need to define A-J as >= 0 and <=9. I also need to say that each color is >= 0 and <=9, but that no color can be equal to another color (purple ≠yellow, orange, etc). some number combinations won't work. Purple and yellow can't be 2 and 5 respectively, because that'd produce a negative number. I'm guessing that there will be more than one possible result. So how do I create an equation that calculates this.
The project is "kWh counter", that is, a simple program that calculates the power usage.The incoming numbers are the Power of the appliance (lightbulb) and the voltage (230/120).The formula is W=P*t that is multiplication of the power and the time it is used.I thought to connect it with a timer and the passing secconds multyply with the power, and, write the ussage on a label.This would be something like a simple digital power counter.Note that the voltage is not necesary.I am from europe where the standards are 230V.
View 7 RepliesMy assignment is to get the Get Monthly Income (Num1)Get Monthly Home Rent/Mortgage (Num2) Get Other Monthly Payments (alimony, child support, student loans) (Num3) Display Allowable Monthly Car Payment Display Maximum Car Value (interest rate based on credit) (answer) Public Class Form1
[Code]...
What I need to do is automatically generate a specific PIN number based on the current date. The formula goes like this: MMDD + 1234 = PIN. (ex. Date = 3/26/2012 -> 0326 + 1234 = 1560; With 1560 being the PIN number. I then need the PIN number to display as text, but that's the easy part, I really just need assistance with getting the date information in the proper format for the equation.
View 2 Repliesafter a lot of research on formatting Maths equations, apparently using MS equation edior is the easiest way to do it. But, I have no idea how to use it in VS 2008.
View 2 RepliesI am rotating a picture dependant on the mousemove.
Private Sub PictureBox1_MouseMove(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles PictureBox1.MouseMove
[code]...
To simplify the part I am having problems with: rotationX = CurrentPositionX + ((InitialPositionX - MousePositonX) / SlowDownDivisor)
As an example, this occurs in both X and Y; If I click and drag in the X + Direction and release the mouse button it does exactly what I want, rotation in the positive direction. If I click and drag in the X + Direction and then drag in the X - direction, the rotation continues to be positive, it doesn't reverse. If I release the button and then click again and move in the X - direction the rotation is negative as it should, but it will continue to rotate in the negitive direction until the button is release.