The basic concept behind this code is that whenever it runs, the quantity from an element decreases and the quantity from the same element, but from a different array, increases. For whatever reason, the second while loop only runs once and stops. For example, if total1 = 11 and total2 = 0, the first time the code is executed, total1 = 10 and total2 = 1. However after that, total1 = 9 and total2 = 1 and so on. Can anyone tell me what is wrong with my code? Any and all help would be appreciated.
<%
count = 0
do while NOT rs3.EOF
if rs3("ITEM_NO") = itemnum then
qtyArray(count) = qtyArray(count) - qtyreq
end if
if qtyArray(count) >= 0 and rs3("ITEM_NO") = itemnum then
total1 = total1 - qtyreq
end if
count = count + 1
rs3.MoveNext
loop
rs3.MoveFirst
pickcount = 0
do while NOT rs3.EOF
if qtyPick(pickcount) >= 0 and rs3("ITEM_NO") = itemnum then
qtyPick(pickcount) = qtyPick(pickcount) + qtyreq
total2 = total2 + qtyreq
end if
rs3.MoveNext
pickcount = pickcount + 1
loop
%>
total2 = total2 + qtyreq
Please make sure "qtyreq" variable is not 0 and really adds +1 to your total2.
There is a line on your second loop pickcount = pickcount + 1. Just move this line above the line rs3.MoveNext of your second loop
Related
So this is the code:
int test ( int n)
{
if (n ≤2) return 1;
else return test(n-2) * test(n-2);
}
I'm not confident in how to reason about this recursive function. I tried mapping the N value to the recursion depth like so:
N = 2 -> 0 recursions
N = 4 -> 2
N = 8 -> 14
But to be honest I'm not sure this gets me anywhere (and just thinking about test(16) hurts my head.
Let's start by writing out a recurrence relation for the total number of calls made:
T(0) = T(1) = T(2) 1, since there's one total call (the initial call).
T(n+2) = 2T(n) + 1, since there's one call for the initial call, plus two recursive calls to problems of size n.
Let's start by looking at the case where n is even. Then
T(0) = 1
T(2) = 1
T(4) = 2T(2) + 1 = 3
T(6) = 2T(4) + 1 = 7
T(8) = 2T(6) + 1 = 15
T(9) = 2T(8) + 1 = 31
Except for the 0 case, it looks like these values take on the pattern 1, 3, 7, 15, 31, etc. Notice that each of these is one less than a power of two: 1 = 2 - 1, 3 = 4 - 1, 7 = 8 - 1, etc. We can guess that what we're looking at has something to do with powers of two.
Going back to our sequence, we might make a guess that
T(2) = 1 = 21 - 1
T(4) = 3 = 22 - 1
T(6) = 7 = 23 - 1
...
T(2n) = 2n - 1
So if n is even, we have T(n) = 2n/2 - 1 = (√2)n - 1. You can formalize this using a proof by induction.
For the odd case, we basically get the same thing:
T(1) = 1
T(3) = 2T(1) + 1 = 3
T(5) = 2T(3) + 1 = 7
T(7) = 2T(5) + 1 = 15
T(9) = 2T(7) + 1 = 31
...
T(2n+1) = 2n - 1
So if n is even, then T(n) = 2(n-1)/2 - 1. Again, you can prove this by induction to formalize things if you'd like.
Hi I'm new to python and programming in general. I am trying write a program that uses a while loop to add integers from 1 to the number entered. the program also has to give an error statement if the user enters a 0 or negative number. So far the integers add up and the error statement works but the program is not looping, it only asks the user to input a number one time. Please help. This is my source code so far. Thanks
x = int(input("Enter a positive number not including zero:" ))
total = 0
n = 1
while n <= x:
total = total + n
n = n + 1
# prints the total of integers up to number entered
print("Sum of integers from 1 to number entered= ",total)
if x <= 0 or x == -x:
print ("invalid entry")
Try this code...
op='y'
while op=='y':
x = int(input("Enter a positive number not including zero:" ))
total = 0
n = 1
if x > 0:
while n <= x:
total = total + n
n = n + 1
# prints the total of integers up to number entered
print("Sum of integers from 1 to number entered= ",total)
else:
print ("invalid entry")
op = raw_input("Are you want to continue this operation (y/n):" )
Put your whole code this way
done = False
while not done:
//your entire code here except the last 2 lines
if x > 0:
done = True
I have a vector of widths,
ws = c(1,1,2,1,3,1)
From this vector I'd like to have another vector of this form:
indexes = c(1,2,3,5,6,7,9,11,12)
In order to create such vector I did the following for loop in R:
ws = c(1,1,2,1,3,1)
indexes = rep(0, sum(ws))
counter = 1
counter2 = 1
last = 0
for(i in 1:length(ws))
{
if (ws[i] == 1)
{
indexes[counter] = counter2
counter = counter + 1
} else {
for(j in 1:ws[i])
{
indexes[counter] = counter2
counter = counter + 1
counter2 = counter2+2
}
counter2 = counter2 - 2
}
counter2 = counter2+1
}
The logic is as follows, each element in ws specifies the respective number of elements in index. For example if ws is 1, the respective number of elements in indexes is 1, but if ws is > 1, let us say 3, the respective number of elements in index is 3, and the elements are skipped 1-by-1, corresponding to 3,5,7.
However, I'd like to avoid for loops since they tend to be very slow in R. Do you have any suggestions on how to achieve such results only with vector operations? or some more crantastic solution?
Thanks!
Here's a vectorized one-liner for you:
ws <- c(1,1,2,1,3,1)
cumsum((unlist(sapply(ws, seq_len)) > 1) + 1)
# [1] 1 2 3 5 6 7 9 11 12
You can pick it apart piece by piece, working from the inside out, to see how it works.
Using a random library with these functions:
randomChance(p) Returns true with the probability indicated by p.
randomInteger(low, high) Returns a random integer in the range low to high, inclusive.
what is the easiest way to implement a "random selector" that takes consideration of percentage, 1/4 or 1/3 etc... I got a array with key/value pairing. For example "a" migth have the value 2 and "b" have the value 2. 1/2 chance for both.
The max value will be the size of the array, cause it only contains unique items. The randomChance() function ranges between 0.0 - 1.0 where 1 = 100%. If my array size is, say 4. What is the best way of "letting 4 be 1".
Lets say you have:
a = 2, b = 2, c = 1, d = 3
now make it:
a = 2, b = 4, c = 5, d = 8
Create a random number from 1 to MaxVal (value of the last key, 8 in this example). Select the first Key where Value >= RandomNum
EDIT
I made a small VB.Net to show the algorithm and how it works. The code is not meant to be: Good, elegant, performant or readable.
Module Module1
Private Class Value
Public vOrg, vRecalc, HitCount As Integer
Public Key As String
Public Sub New(s, v1, v2, c)
Key = s : vOrg = v1 : vRecalc = v2 : HitCount = c
End Sub
End Class
Sub Main()
' set initial values
Dim KVP() As Value = {New Value("A", 2, 0, 0),
New Value("B", 2, 0, 0),
New Value("C", 1, 0, 0),
New Value("D", 3, 0, 0)}
' recalc values
For i = 0 To KVP.Length - 1
If i = 0 Then KVP(0).vRecalc = KVP(0).vOrg Else KVP(i).vRecalc = KVP(i).vOrg + KVP(i - 1).vRecalc
Next
' do test
Dim r As New Random
Dim runs As Integer = 1000 * 1000, maxval As Integer = KVP(KVP.Length - 1).vRecalc
For i = 1 To runs
Dim RandVal = r.Next(1, maxval + 1)
Dim chosen As Integer = (From j In Enumerable.Range(0, KVP.Length) Where KVP(j).vRecalc >= RandVal Take 1 Select j)(0)
KVP(chosen).HitCount += 1
Next
' ouput results
For Each kv In KVP
Console.WriteLine("{0} was chosen with {1:F3} propability, expected was {2:F3}", kv.Key, kv.HitCount / CDbl(runs), kv.vOrg / CDbl(maxval))
Next
Console.ReadLine()
End Sub
End Module
An output sample:
A was chosen with 0.250 propability, expected was 0.250
B was chosen with 0.251 propability, expected was 0.250
C was chosen with 0.124 propability, expected was 0.125
D was chosen with 0.375 propability, expected was 0.375
just multiply the randomChance() outcome and the array length together. It'll give you the index in the range [0,array_length-1] which you can use to access the array
array_index = (unsigned int)(randomChance(p) * (array_length - 1));
maybe you mean "letting 3 to be 1" (not 4) in your example. The last index of an array of length 4 is 3.
I have a 10 period cost curve table below. How do I programmatically collapse/condense/shrink this to 4 periods. I'm using VBA but I should be able to follow other languages. The routine should work for whatever period you pass to it. For example, if I pass it a 7 it should condense the percentages to 7 periods. If I pass it 24 then expand the percentages to 24 periods, spreading the percentages based on the original curve. Any help or example will be appreciated. Thanks...
ORIGINAL
Period Pct
1 10.60%
2 19.00%
3 18.30%
4 14.50%
5 10.70%
6 8.90%
7 6.50%
8 3.10%
9 3.00%
10 5.40%
COLLAPSED
Period Pct
1 38.75%
2 34.35%
3 16.95%
4 9.95%
EDITED: I've added sample code below as to what I have so far. It only works for periods 1, 2, 3, 5, 9, 10. Maybe someone can help modify it to work for any period. Disclaimer, I'm not a programmer so my coding is bad. Plus, I have no clue as to what I'm doing.
Sub Collapse_Periods()
Dim aPct As Variant
Dim aPer As Variant
aPct = Array(0.106, 0.19, 0.183, 0.145, 0.107, 0.089, 0.065, 0.031, 0.03, 0.054)
aPer = Array(1, 2, 3, 5, 9, 10)
For i = 0 To UBound(aPer)
pm = 10 / aPer(i)
pct1 = 1
p = 0
ttl = 0
For j = 1 To aPer(i)
pct = 0
k = 1
Do While k <= pm
pct = pct + aPct(p) * pct1
pct1 = 1
p = p + 1
If k <> pm And k = Int(pm) Then
pct1 = (pm - Int(pm)) * j
pct = pct + (pct1 * aPct(p))
pct1 = 1 - pct1
End If
k = k + 1
Loop
Debug.Print aPer(i) & " : " & j & " : " & pct
ttl = ttl + pct
Next j
Debug.Print "Total: " & ttl
Next i
End Sub
I would like to know how this is done also using an Integral? This is how I would have done it - perhaps it's a longhand/longwinded method but I'd like to see some better suggestions.
It's probably easier to see the method in Excel first using the LINEST function and Named ranges. I've assumed the function is logarithmic. I've outlined steps [1.] - [5.]
This VBA code then essentially replicates the Excel method using a function to pass 2 arrays, periods and a return array that can be written to a range
Sub CallingProc()
Dim Periods As Long, returnArray() As Variant
Dim X_Values() As Variant, Y_Values() As Variant
Periods = 4
ReDim returnArray(1 To Periods, 1 To 2)
With Sheet1
X_Values = Application.Transpose(.Range("A2:A11"))
Y_Values = Application.Transpose(.Range("B2:B11"))
End With
FGraph X_Values, Y_Values, Periods, returnArray 'pass 1D array of X, 1D array of Y, Periods, Empty ReturnArray
End Sub
Function FGraph(ByVal x As Variant, ByVal y As Variant, ByVal P As Long, ByRef returnArray As Variant)
Dim i As Long, mConstant As Double, cConstant As Double
'calc cumulative Y and take Ln (Assumes Form of Graph is logarithmic!!)
For i = LBound(y) To UBound(y)
If i = LBound(y) Then
y(i) = y(i)
Else
y(i) = y(i) + y(i - 1)
End If
x(i) = Log(x(i))
Next i
'calc line of best fit
With Application.WorksheetFunction
mConstant = .LinEst(y, x)(1)
cConstant = .LinEst(y, x)(2)
End With
'redim array to fill for new Periods
ReDim returnArray(1 To P, 1 To 2)
'Calc new periods based on line of best fit
For i = LBound(returnArray, 1) To UBound(returnArray, 1)
returnArray(i, 1) = UBound(y) / P * i
If i = LBound(returnArray, 1) Then
returnArray(i, 2) = (Log(returnArray(i, 1)) * mConstant) + cConstant
Else
returnArray(i, 2) = ((Log(returnArray(i, 1)) * mConstant) + cConstant) - _
((Log(returnArray(i - 1, 1)) * mConstant) + cConstant)
End If
Next i
'returnArray can be written to range
End Function
EDIT:
This VBA code now calculates the linear trend of the points either side of the new period reduction. The data is returned in a 2dimension array named returnArray
Sub CallingProc()
Dim Periods As Long, returnArray() As Variant
Dim X_Values() As Variant, Y_Values() As Variant
Periods = 4
ReDim returnArray(1 To Periods, 1 To 2)
With Sheet1
X_Values = Application.Transpose(.Range("A2:A11"))
Y_Values = Application.Transpose(.Range("B2:B11"))
End With
FGraph X_Values, Y_Values, returnArray 'pass 1D array of X, 1D array of Y, Dimensioned ReturnArray
End Sub
Function FGraph(ByVal x As Variant, ByVal y As Variant, ByRef returnArray As Variant)
Dim i As Long, j As Long, mConstant As Double, cConstant As Double, Period As Long
Period = UBound(returnArray, 1)
'calc cumulative Y
For i = LBound(y) + 1 To UBound(y)
y(i) = y(i) + y(i - 1)
Next i
'Calc new periods based on line of best fit
For i = LBound(returnArray, 1) To UBound(returnArray, 1)
returnArray(i, 1) = UBound(y) / Period * i
'find position of new period to return adjacent original data points
For j = LBound(x) To UBound(x)
If returnArray(i, 1) <= x(j) Then Exit For
Next j
'calc linear line of best fit between existing data points
With Application.WorksheetFunction
mConstant = .LinEst(Array(y(j), y(j - 1)), Array(x(j), x(j - 1)))(1)
cConstant = .LinEst(Array(y(j), y(j - 1)), Array(x(j), x(j - 1)))(2)
End With
returnArray(i, 2) = (returnArray(i, 1) * mConstant) + cConstant
Next i
'returnarray holds cumulative % so calc period only %
For i = UBound(returnArray, 1) To LBound(returnArray, 1) + 1 Step -1
returnArray(i, 2) = returnArray(i, 2) - returnArray(i - 1, 2)
Next i
'returnArray now holds your data
End Function
Returns:
COLLAPSED
1 38.75%
2 34.35%
3 16.95%
4 9.95%