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I want to write an equation solver, Like Microsoft Student Graphing Calculator(Equation Solving tab).
I wanna solve equations like this :
4.x = 2.x + 2
Can anybody give me some sample code, or any suggestion
Thank you
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Hum, that's not an easy task. You'll need to parse the string first. A parser example can be found in this[^] article.
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I've written my parser already, but I don't have any idea how to solve an equation.In equation there is no value for X variable.
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IMHO, you would have to parse the string and put the elements on to a stack.
I did this sometime back so can't remember exactly but this is the logic that I used.
If you get an operand pop one element from the stack .
If you get an operator pop two elements from the stack , perform the operation and again put the result on the stack . Go on doing the same operation until the stack is empty
Somethings seem HARD to do, until we know how to do them.
_AnShUmAn_
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How can I run a stored procedure(SQL Server 2005) with parameters read from a dialog in VC6.0 ++ standard edition?
-- modified at 3:56 Thursday 27th July, 2006
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Can u explain a little more?
nave
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Naveen R wrote: Can u explain a little more?
I have a SQL Server database in which I have a table containing name fields, data fields. I have a menu item wich says: filter by date, the menu opens a dialog in which u can select the day, month, hour.... I want to create a stored procedure to take these parameters and perform the filter for me.
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Use catsets.cpp/h provided my microsoft.
Also There are some extension classes available in Code project it self.
"http://www.codeproject.com/database/myrecordset.asp"
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1. I can't understand the meanning of the parameters in function DrawIndexPrimitive & DrawIndexPrimitiveUp &SetIndices. Could someone Illustrate me witch some very clearly example.
2. I dont understand format of texture with format DXTn.
I always get error when i try to access directly to it data.
For example:
For(y = 0; y < Height; y++){
memcpy((char *) lockedrect.pBit + y* lockecrect.pPitch,
mydata,
Width * sizeinbyteofpixel)
}
I dont known sizeinbyteofpixel is, i try with 1 and get error.
Someone tell me how i compute sizeinbyteofpixel.
And tell me why i alway get error.
Because i don't understand format of compressed texture.
I'm very thanks if some one tell me some good DirectX book to download ( free, i'm not have credit card to buy).
Or I'm very happy if someone share me with your favorite book
Thanks
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Thanks for your suggest.
Unfortunately i have all these books,
but I think it's not enough for me to understand.
Anyway, thank you.
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Im not an expert with DirectX technologies...if none of these books can solve your problem, sorry...
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Dear Sir,
I am using CLayout helper class to resize all my Formview.
When I change the backcolor of all STATIC control, i have a problem. The color is applied round the text only, else where on the control the system color remain like that.
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mikobi wrote: When I change the backcolor of all STATIC control,
How u changed it? in CTL_COLOR message?
nave
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this is what I do:
HBRUSH CPayrollView::OnCtlColor(CDC* pDC, CWnd* pWnd, UINT nCtlColor)
{
HBRUSH hbr = COleDBRecordView::OnCtlColor(pDC, pWnd, nCtlColor);
if( nCtlColor == CTLCOLOR_STATIC)
{
// seulement pour le static que tu veux modifier
pDC->SetTextColor (RGB(128,0,0)); // texte rouge fonce
pDC->SetBkColor (RGB(188,143,143)); // fond noir
} ;
if( nCtlColor == CTLCOLOR_DLG)
{
static CBrush MyBrush;
if( !MyBrush.m_hObject )
{
MyBrush.CreateSolidBrush( RGB(188,143,143));
}
return MyBrush;
}
return hbr;
}
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Like the way u return a MyBrush for the CTLCOLOR_DLG, U have to return a brush for the CTLCOLOR_STATIC also.
HBRUSH CPayrollView::OnCtlColor(CDC* pDC, CWnd* pWnd, UINT nCtlColor)
{
HBRUSH hbr = COleDBRecordView::OnCtlColor(pDC, pWnd, nCtlColor);
static CBrush MyBrush;
if( !MyBrush.m_hObject )
{
MyBrush.CreateSolidBrush( RGB(188,143,143));
}
if( nCtlColor == CTLCOLOR_STATIC)
{
// seulement pour le static que tu veux modifier
pDC->SetTextColor (RGB(128,0,0)); // texte rouge fonce
pDC->SetBkColor (RGB(188,143,143)); // fond noir
return MyBrush;
} ;
if( nCtlColor == CTLCOLOR_DLG)
{
return MyBrush;
}
return hbr;
}
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OK thanks a lot for your Help
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Execuse me sir;
I try the same for a button, it don't work :
HBRUSH hbr = COleDBRecordView::OnCtlColor(pDC, pWnd, nCtlColor);
static CBrush MyBrush;
if( !MyBrush.m_hObject )
{
MyBrush.CreateSolidBrush( RGB(188,143,143));
}
if( nCtlColor == CTLCOLOR_STATIC)
{
// seulement pour le static que tu veux modifier
pDC->SetTextColor (RGB(128,0,0)); // texte rouge fonce
pDC->SetBkColor (RGB(188,143,143)); // CTLCOLOR_BTN
return MyBrush;
} ;
if( nCtlColor == CTLCOLOR_DLG)
{
return MyBrush;
}
if( nCtlColor == CTLCOLOR_BTN)
{
return MyBrush;
}
return hbr;
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mikobi wrote: I try the same for a button, it don't work :
for button it will not work. If u want to change the color of the button, u have to Draw it by ur self. This can be done by giving(BS_OWNERDRAW) style to the button. U can find enough articles explaining this. Try googling Owner Draw Button.
nave
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Supposing I declare a char array like
char p[20] = {"Hello"} ;
Where will this array of chars get created? In the Heap or the Stack? When the function where this array is declared goes out of scope, will the char array be automatically deleted or will I have to explicitly delete it?
---
Hakuna-Matada
It means no worries for the rest of your days...
It's our problem free, Philosophy
<marquee behavior="alternate" scrollamount="5" scrolldelay="50">
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it is created in the stack and it will be deleted automatically
never say die
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Everything is allocated on stack unless you explicitly allocate with new , malloc , realloc ...
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or if its global
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When I try to use setdlgitemtext to place some text into the EDIT box,
it will cause the flickering problem. Is there any method to solve it?
Please help! Many thanks!
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You could try SetRedraw(false), update your control's text, then SetRedraw(true), then Invalidate the control. Not sure if it has any affect on edit controls, but works for tree and list controls.
- S
50 cups of coffee and you know it's on!
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