Following VB.Net code does not return the expected result:
Dim sum As Single = 535353
Dim vat As Single = Math.Round(sum * 0.19, 2)
Dim total As Single = Math.Round(sum + vat, 2)
Debug.WriteLine(String.Format("sum: {0:c2}, vat: {1:c2}, total: {2:c2}", sum, vat, total))
vat is correctly set to 101717.07, but the result of "total" is 636070.063.
Why does the last Math.round function returns 3 digits, and the wrong result?
Try it using Double
Dim sum As Double = 535353
Dim vat As Double = Math.Round(sum * 0.19, 2)
Dim total As Double = Math.Round(sum + vat, 2)
' sum 535353.0 Double
' total 637070.07 Double
' vat 101717.07 Double
Related
I am having issues trying to make a calculator that accurately calculates deposits plus the amount of interest that is added monthly. I dont know how to incorporate a loop that can add monthly deposits to total deposits, then adds the total deposits plus total interest times the interest rate / 100 / 12 to the total deposits. Here is what I have so far. Sorry am super new to VB !
Dim intMonthlyDeposit As Interger
Dim intMonthsTotal As Integer
Dim intAnnualRate As Interget
Dim decTotalDeposits As Decimal
Dim decTotalInterest As Decimal
Dim decTotalTotal As Decimal
Try
intMonthlyDeposit = CInt(txtMonthlyDeposits.Text)
intMonthsTotal = CInt(txtMonths.Text)
decAnnualRate = CDec(txtAnnualRate.Text)
decTotalDeposits = 0
decTotalInterest = 0
decTotalTotal = 0
decTotalDeposits = decMonthlyDeposit * intMonthsTotal
decTotalInterest = decTotalDeposits * (decAnnualRate / 100)
decTotalTotal = decTotalDeposits + decTotalInterest
lblTotDeposit.Text = decTotalDeposits.ToString("C")
lblTot.Text = decTotalTotal.ToString("C")
lblTotInterest.Text = decTotalInterest.ToString("C")
Catch ex As Exception
MsgBox("Enter a Valid Number")
End Try
End Sub
This is how I implemented the loop for calculating total interest and total deposits correctly.
For index As Integer = 1 To intMonthsTotal Step 1
decTotalDeposits += decMonthlyDeposit
decTotalInterest += (decTotalDeposits + decTotalInterest) * ((decAnnualRate / 100) / 12)
I am trying to implement a simple calculation to output Total Price using Visual Basic.NET
I want to read Original Price and Shipping Weight then use it in the calculation. The problem is,
When I enter any values, both variables will return only first digit
For example, if enter 23 it will return 2
Dim originalPrice As Double
Dim commissionPrice As Double
Dim shippingWeight As Double
Dim totalPrice As Double
Console.Write("Enter Original Price: ")
originalPrice = Double.Parse(Console.ReadLine(originalPrice))
Console.Write("Enter Shipping Weight: ")
shippingWeight = Double.Parse(Console.ReadLine(shippingWeight))
shippingWeight = shippingWeight * 7
If (originalPrice + shippingWeight >= 200) Then
commissionPrice = (originalPrice + shippingWeight) * 0.03
Else
commissionPrice = 5
End If
totalPrice = commissionPrice + originalPrice + shippingWeight
Console.WriteLine(originalPrice)
Console.WriteLine(commissionPrice)
Console.WriteLine(shippingWeight)
Console.WriteLine(totalPrice)
I think that your problem is that you are passing the variable to the Console.read()
In this way should work.
Dim originalPrice As Double
Dim commissionPrice As Double
Dim shippingWeight As Double
Dim totalPrice As Double
Console.Write("Enter Original Price: ")
originalPrice = Double.Parse(Console.ReadLine())
Console.Write("Enter Shipping Weight: ")
shippingWeight = Double.Parse(Console.ReadLine())
shippingWeight = shippingWeight * 7
If (originalPrice + shippingWeight >= 200) Then
commissionPrice = (originalPrice + shippingWeight) * 0.03
Else
commissionPrice = 5
End If
totalPrice = commissionPrice + originalPrice + shippingWeight
Console.WriteLine(originalPrice)
Console.WriteLine(commissionPrice)
Console.WriteLine(shippingWeight)
Console.WriteLine(totalPrice)
Console.Read()
When I generate random numbers, I sometimes get (not always) the following error:
Run-time error '13': type mismatch.
on line Z = Sqr(time) * Application.NormSInv(Rnd()) (and the end of the second for loop).
Why do I get this error?
I think it has something to do with the fact that it contains Rnd().
Sub asiancall()
'defining variables
Dim spot As Double
Dim phi As Integer
Dim rd_cont As Double
Dim rf_cont As Double
Dim lambda As Double
Dim muY As Double
Dim sigmaY As Double
Dim vol As Double
Dim implied_vol As Double
Dim spotnext As Double
Dim time As Double
Dim sum As Double
Dim i As Long
Dim mean As Double
Dim payoff_mean As Double
Dim StDev As Double
Dim K As Double
Dim Egamma0 As Double
Dim mulTv As Double
Dim prod As Double
Dim U As Double
Dim Pois As Double
Dim Q As Double
Dim Z As Long
Dim gamma As Double
Dim payoff As Double
Dim payoff_sum As Double
Dim secondmoment As Double
Dim j As Long
Dim N As Long
Dim mu As Double
Dim sum1 As Double
'read input data
spot = Range("B3")
rd_cont = Range("C5")
rf_cont = Range("C4")
muY = Range("B17")
sigmaY = Range("B18")
lambda = Range("B16")
K = Range("F33")
implied_vol = Range("F35")
N = Range("F34")
vol = Range("B6")
'calculations
sum_BS = 0
payoff_BS = 0
mean_BS = 0
secondmoment_BS = 0
For j = 1 To N
spotnext = spot
spotnext_BS = spot
time = 0
sum1 = 0
time = 184 / (360 * 6)
For i = 1 To 6
' 'Merton uitvoeren
Egamma0 = Exp(muY + sigmaY * sigmaY * 0.5) - 1
mu = rd_cont - rf_cont
mulTv = (mu - lambda * Egamma0 - implied_vol * implied_vol * 0.5) * time
sum = 0
prod = 1
Do While sum <= time
U = Rnd()
Pois = -Log(U) / lambda
sum = sum + Pois
Q = Application.NormInv(Rnd(), muY, sigmaY)
gamma = Exp(Q) - 1
prod = prod * (1 + gamma)
Loop
prod = prod / (1 + gamma)
Z = Sqr(time) * Application.NormSInv(Rnd())
spotnext = spotnext * Exp(mulTv + implied_vol * Z) * prod
sum1 = sum1 + spotnext
Next i
mean = sum1 / 6
payoff = Application.Max(mean - K, 0)
payoff_sum = payoff_sum + payoff
secondmoment = secondmoment + payoff * payoff
Next j
Following up on the community wiki answer I posted, a possible solution is this:
Function RndExcludingZero()
Do
RndExcludingZero = Rnd()
Loop While RndExcludingZero = 0
End Function
Usage:
Z = Sqr(time) * Application.NormSInv(RndExcludingZero())
Rnd() returns values >=0 and <1.
At some point it is bound to return 0. When given 0 as input in Excel, NormSInv returns the #NUM!
Excel error.* When called in VBA via Application.NormSInv(0), it returns a Variant of subtype Error with value "Error 2036" (equivalent to the #NUM! Excel error).
Such Variant/Errors cannot be implicitly coerced to a numerical value (which is what the * operator expects) and thus in this case, you will get the type mismatch error.
You will only get this error when Rnd() happens to return 0, which is consistent with your observation that the error occurs only sometimes.
* This was first remarked by user3964075 in a now defunct comment to the question.
I'm a first year programming student and am trying to make a mortgage payment calculator. Users enter their loan amount and interest rate, select 15 or 30 years for the term length, and their monthly payment should be calculated. I think the math is correct, but I think I'm running into problems with converting data types. The only result I'm able to calculate is "Infinity". I've also tried declaring all variables as Doubles, but no difference.
Below is the piece of code I'm having trouble with, and Option Strict On is included in the full code. Any tips would be greatly appreciated!
Dim decLoanAmount As Decimal
Dim decInterestRate As Decimal
Dim decFifteen As Decimal = 180D
Dim decThirty As Decimal = 360D
Dim decNumberOfMonths As Decimal
Dim dblPayment As Double
Dim decPayment As Decimal
' Did user enter a numeric value?
If IsNumeric(txtLoanAmount.Text) And IsNumeric(txtInterestRate.Text) Then
decLoanAmount = Convert.ToDecimal(txtLoanAmount.Text)
decInterestRate = Convert.ToDecimal(txtInterestRate.Text)
' Is Loan Amount greater than zero?
If decLoanAmount > 0 And decInterestRate > 0 Then
If radFifteen.Checked = True Then
decNumberOfMonths = decFifteen
ElseIf radThirty.Checked = True Then
decNumberOfMonths = decThirty
End If
' Calculate the monthly payments as a double
dblPayment = (decLoanAmount * (decInterestRate / 12 / 100) * (1 + (decInterestRate / 12 / 100) _
^ decNumberOfMonths)) / ((1 + (decInterestRate / 12 / 100) ^ decNumberOfMonths) - 1)
' Convert double to decimal
decPayment = Convert.ToDecimal(decPayment)
' Display monthly payment
lblPayment.Text = decPayment.ToString("C2")
Else
If decLoanAmount < 0 Then
MsgBox("Please enter a valid loan amount.", , "Input error")
End If
If decInterestRate < 0 Then
MsgBox("Please enter a valid interest rate.", , "Input error")
End If
End If
Else
' Display error message if user entered a negative value.
MsgBox("Please enter a numeric value.", , "Input Error")
End If
End Sub
Based on the Wikipedia formula, you aren't doing it correctly. It should look something like this:
dblPayment = (decLoanAmount * (decInterestRate / (12 * 100))) / (1 - (1 + (decInterestRate / (12 * 100))) ^ (-decNumberOfMonths))
Also, this line is weird
decPayment = Convert.ToDecimal(decPayment)
Should be
decPayment = Convert.ToDecimal(dblPayment)
I need to make an auto loan calculator that is only able to calculate 2.3% interest for 84 months. I've never made a calculator that didn't allow a user to input these amounts, so how do I code that part of the calc?
Dim res As Decimal = 100 ' Current value
Dim interest As Decimal = 1.89 / 100 ' 1.89%
For i As Integer = 1 To 89 'Months
Dim amr As Decimal = res * interest
res += amr
Next
MsgBox(res)
Depends on what you want to calculate.. Monthly paiement, equity, what is left to pay ?
Here's the formula to calculate the monthly paiement of a loan
Dim monthlyPaiement As Decimal
Dim loanAmount As Decimal
Dim interestRate As Decimal
Dim loanLengthInMonth As Decimal
loanAmount = 25000
interestRate = 1.9 / 100
loanLengthInMonth = 84
interestRate /= 12 ' Divide by number of month in a year
monthlyPaiement = loanAmount * ((1 + interestRate) ^ loanLengthInMonth) * interestRate / (((1 + interestRate) ^ loanLengthInMonth) - 1)