C / C++ / MFC

Prolem of Access database

2-Sep-08 1:47

This link[^]"> will be of little help...

Regards,
Rane

Re: Timer

knowvc2-Sep-08 1:53

knowvc

2-Sep-08 1:53

Thx's for link

I want to use timer for update DoModal() dailog.Can you help me..

void Crtdlg::Ondo()
{
CT dlg;
dlg.DoModal();

}

And i want to update this dailog every 5mins..

Plz help me

Re: Timer

David Crow2-Sep-08 3:35

David Crow

2-Sep-08 3:35

knowvc wrote:
Can you help me..

Have you bothered to look at SetTimer()?

"Love people and use things, not love things and use people." - Unknown

"The brick walls are there for a reason...to stop the people who don't want it badly enough." - Randy Pausch

Le@rner2-Sep-08 1:28

Le@rner

2-Sep-08 1:28

Hi all,

I m using Access database,and create a connection thru ODBC.

Its working fine when run application,after sum time its gices an error.

"Too many Client Task
Driver’s SOLSetConnectAttr Failed"

please help me for this.

thanks in advance.

IN A DAY, WHEN YOU DON'T COME ACROSS ANY PROBLEMS - YOU CAN BE SURE THAT YOU ARE TRAVELLING IN A WRONG PATH

Re: Prolem of Access database

Rane2-Sep-08 1:38

2-Sep-08 1:38

How many number of connections have you made?.This limitation could be because of the limitation of the Access Driver. Close some connections and try again..

Regards,
Rane

INTEGER CALCULATION

manoj_362-Sep-08 1:03

2-Sep-08 1:03

Hi
I am writing a program in which a function generates Power of 2 .
I would like to generate say
for eg 2^100
But with int or long int i cant store and process the value.
Any Suggestions on storing and how to calculate the value will be of good help

Thanks

Rane2-Sep-08 1:13

2-Sep-08 1:13

Use unsigned long long datatype and it can hold values up to 18,446,744,073,709,551,615.

Regards,
Rane

manoj_362-Sep-08 7:49

2-Sep-08 7:49

what if the value exceeds the above specified limit ??

David Crow2-Sep-08 7:51

David Crow

2-Sep-08 7:51

Then you'll need to treat the numbers as strings instead.

"Love people and use things, not love things and use people." - Unknown

"The brick walls are there for a reason...to stop the people who don't want it badly enough." - Randy Pausch

Mark Salsbery2-Sep-08 8:06

Mark Salsbery

2-Sep-08 8:06

Rane wrote:
Use unsigned long long datatype

That only leaves 37 more bits required for the OP to get
an integer representation of 2^100 Roll eyes | :rolleyes:

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

manoj_364-Sep-08 17:44

4-Sep-08 17:44

Can you just give a sample code for the conversion.
Thanks in advance

Mark Salsbery5-Sep-08 4:58

Mark Salsbery

5-Sep-08 4:58

I'm not sure what you're trying to do.

Your 2^100 example would take a 101 bit integer - there's
no built in C/C++ integer type that's that big.

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

manoj_365-Sep-08 5:48

5-Sep-08 5:48

I am doing a calculation, in which i have to calculate the power of say(for e.g 2 ^ 100 , 2 ^150 etc) .
And i have to see if that 2^100 has a pattern of 777 in it.

so i am thinking of a logic to store this huge integer number.
Even if i use long int i can maximum store up to 2^64.

But i am thinking of storing them in character array ....

Member 419459315-Sep-08 13:05

Member 4194593

15-Sep-08 13:05

manoj_36 wrote:
I am doing a calculation, in which i have to calculate the power of say(for e.g 2 ^ 100 , 2 ^150 etc) .
And i have to see if that 2^100 has a pattern of 777 in it.

Let me start with a word of warning about the size of numbers you will be working with. You have not stated the upper limit of the power of 2 you are working with, but if you use, for example, 2 ^ 65536, this will give you a number of 2.x...e+19728 (try this with calculator using 2 x^y 65536). That means that the decimal number to represent this value will have 19729 digits. This number in binary will have 65536 bits, or 8192 bytes, or 2048 unsigned integers.

Setting the value of a power of 2 is trivial. Start by defining an array of unsigned integers which can contain the largest binary number you expect (plus several more - I'll explain later). Do not try to create 2 ^ 100 by multiplying 2 by 2 100 times, use math. A power of 2 in binary is nothing but a single bit positioned in the binary number, starting with the least significant bit for 2 ^ 0, the next most significant bit for 2 ^ 1, etc. To multiply two powers of 2, just add their exponents, e.g. (2 ^ 10) * (2 ^ 15) = 2 ^ 25. To express the binary value of a power of 2, start by zeroing the array of unsigned integers, then divide the power of 2 by 32, and also save the remainder (the mod 32). Set an unsigned integer to a value of 1, then left shift it by the modulo value (0 to 31 places), then save it in the array at the index of the quotient of the division.

As can be seen from the above, it is trivial to create such a binary value, but now, how to express it as a decimal value so you can scan the result for a string of "777" (remember the bit about how big this string could get). Also take into account array indexing - are you indexing from 0 to n-1 or indexing from 1 to n.

To convert this number to decimal, start from the top end of the array (the most significant end) which should contain a couple of zero values at the top. The reason for these extra zero values is that the division process will not use up each unsigned integer, and the remainder creeps up. When dividing a binary number by a binary number, the number of bits of the resulting quotient will equal the difference between the number of bits in the dividend less the number of bits in the divisor. We will divide this huge binary number (thousands of unsigned integers) by a large unsigned integer, namely 10 ^ 9 (the largest power of 10 that will fit in an unsigned integer).
This will result in a quotient that is one unsigned integer less than the dividend, and a remainder that is less than 10 ^ 9. Save this remainder in another array of unsigned integers. Repeat the process, dividing the new quotient by 10 ^ 9 to create a shorter quotient and a new remainder, saving the remainders in the new array. Continue this process until the resultant quotient is 0 and the last remainder has been saved. Remember the bit about 19729 digits, well, 19729 / 9 = 2192 so the remainder array will have to be at least that long.

Now to create the decimal number. Access each of the saved remainders, starting with the first one saved. This remainder contains the least significant 9 digits of the decimal number, so you will start saving the decimal number in reverse, starting at character (count of remainders * 9). Actually, save a terminating null character 1 character past that, then start the conversion. Divide the remainder 9 times by a value of 10, saving the quotient for each division, and using the remainder for each division to access a decimal character in a string of "0123456789". Save each character in the target decimal string, each character in front of the last saved character (the first in front of the terminating null). Repeat the process for each of the remainders. There will potentially be leading zero characters at the head of the string which can be ignored for your pattern search application (skip by the leading zeros if you intend to print out this string, but remember that 19728 characters takes 247 lines of 80 characters to print - probably not what you want to do).

I'm not sure what your coding looks like and whether or not you can escape to assembly to do the division calculation, but escaping to assembly sure will speed up the entire process rather than trying to cast a moving indexed value as a unsigned long integer. I can help with this if using assembly is possible. Note: I know C, some C++, but really am a MASM coder.

Dave.

manoj_3614-Sep-08 19:33

problem in acessing bluetooth dongle from c++ problem

14-Sep-08 19:33

can some body give me the soln ?

manju23reddy2-Sep-08 1:01

manju23reddy

2-Sep-08 1:01

hi i have a bluetooth dongle and a program to serach all the devices using bluetooth,
but the problem is findFirstDevice() function always returns null so it fails in searching but, i know that micrososft will support only a few dongles, mine is broadcom bcm2045a, but is there any alternative than this i came to know that we can use serial communication, but i have a doubt that by using serial com can we able to discover the devices and also can we able to connect to specified device... and if u have any code and tutorials related to this topic plz provide me the link...

Re: problem in acessing bluetooth dongle from c++ problem

auralius manurung2-Sep-08 16:13

auralius manurung

2-Sep-08 16:13

i've never done programming using bluetooth before...
but i suggest you ro google about mobile phone programming...
find beeter API may be...
try this : "http://mobile.liveshere.net/articles/viewarticle.php?id=19"

Application stopped working automaticaly.

Le@rner2-Sep-08 0:52

Le@rner

2-Sep-08 0:52

Hi all,

i run my application after sum time its stop working and generate a message.
Label of message is "Microsoft windows"

message ::"Application file has stop working"
"Window can check online for a solution of the problem"

three options are available in message window.

"1. check online for a solution and close program"
"2. close the program"
"3. Debug the program"

please tell me how can i solve this.

thank in advance.

IN A DAY, WHEN YOU DON'T COME ACROSS ANY PROBLEMS - YOU CAN BE SURE THAT YOU ARE TRAVELLING IN A WRONG PATH

Re: Application stopped working automaticaly.

Rane2-Sep-08 1:19