division

division and multiplication by power of 2

99封情书 提交于 2019-12-06 08:04:46
I read in a paper that division and multiplication of a number by a power of 2 is a trivial process. I have searched a lot of internet for the explanation but doesn't get it. Can any one explain in easy words what does this actually meant to say. Vlad It is trivial from the bit operations perspective. Multiplying by 2 is equivalent to a shift left by 1 bit, division is a right shift. similarly it is the same trivial to multiply and divide by any power of 2. int a = 123; // or in binary format: a = 0b01111011; assert (a * 2) == (a << 1); // 2 = 2^1, (a << 1) = 11110110 assert (a / 2) == (a >> 1

How scale is defined when decimal and bigint are divided?

百般思念 提交于 2019-12-06 07:53:07
I have value A of type DECIMAL(19,8) - the scale is 8 , so the number of decimal digits that will be stored to the right of the decimal point is 8 . Now, I am dividing A on B , where B is BIGINT . For, example: SELECT CAST(3 AS DECIMAL(19, 8)) / CAST(27 AS BIGINT) -- 0.111111111111111111111111111 ,CAST(300 AS DECIMAL(19, 8)) / CAST(27 AS BIGINT) -- 11.111111111111111111111111111 ,CAST(75003 AS DECIMAL(19, 8)) / CAST(13664400 AS BIGINT) -- 0.005488934750153684025643277 the output values are with length: 29 , 30 , 29 respectively. Could anyone tell why the length of the value for the three

bcdiv using very small float with scientific notation cause “Division by zero” error

我是研究僧i 提交于 2019-12-06 04:09:55
Using bcdiv, i can't divide with small float using scientific notation : Working code : bcscale(30); $a = '1' ; $b = '0.00000001'; $result = bcdiv($a, $b); var_dump($result); Results in : string(20) "100000000.0000000000" Non-working code : bcscale(30); $a = '1' ; $b = '1e-8'; $result = bcdiv($a, $b); var_dump($result); Results in : Warning: bcdiv() [function.bcdiv]: Division by zero in C:\wamp\www\utilitaires\test_bcdiv.php on line XX NULL How can i do this division properly, with the less precision loss ? That is because, actually, bcmath doesn't support scientific notation. It isn't

How does division work in MIX?

≡放荡痞女 提交于 2019-12-06 03:23:23
问题 Can someone explain to me how division in MIX (from TAOCP by Knuth) works on a byte-to-byte basis? rA = |-| . . . .0| rX = |+|1235|0|3|1| The memory location 1000 contains |-|0|0|0|2|0| . When you execute the operation DIV 1000 the registers become rA = |+|0|617|?|?| rX = |-|0|0|0|?|1| Now I understand the signs on rA and rX , but in what order are the bytes of rAX filled and which divisions are done? If DIV 1000 leads to every bit divided by 2, then I would expect rAX = |+|617|0|1|0|-|0|1|0

Dividing an Two number Using Loop Statement

吃可爱长大的小学妹 提交于 2019-12-06 02:00:34
hi i'm doing a java activity that will divide the two given numbers without using the "/" operator. I want to use a loop statement. System.out.print("Enter Divident: "); int ans1 = Integer.parseInt(in.readLine()); System.out.print("Enter Divisor: "); int ans2 = Integer.parseInt(in.readLine()); The output is: Enter Dividend: 25 Enter Divisor 5 5 How can solve this without using this "ans1/ans2" if you really want to use loop to divide two numbers, you can write it like code below int c=0; while(ans1 >= ans2){ ans1 -= ans2; c++; } after loop c equals quotient and ans1 equals reminder of division

Doctest not recognizing __future__.division

假装没事ソ 提交于 2019-12-05 20:58:11
问题 I have the following doctest written x.doctest : This is something: >>> x = 3 + 4 foo bar something else: >>> from __future__ import division >>> y = 15 >>> z = int('24') >>> m = z / y >>> print (m) 1.6 But when I ran python -m doctest x.doctest on python 2.7.11, the doctest didn't recognize from __future__ import division : ********************************************************************** File "x.doctest", line 11, in x.doctest Failed example: print (m) Expected: 1.6 Got: 1 ************

Overflow Exception when dividing two decimals in .NET

Deadly 提交于 2019-12-05 15:34:49
I'm having an issue trying to divide two decimals and then display the result. Annoyingly this is only happening on our server, and it appears to work perfectly fine if I run the code locally. This is the code that I am trying to run decimal dOne = -966.96M; decimal dTwo = 2300M; decimal dResult = Decimal.Round((dOne / dTwo), 28, MidpointRounding.AwayFromZero); The resulting number (as generated from windows calculator) is -0.43346086956521739130434782608696 This always results in an overflow exception: System.OverflowException: Value was either too large or too small for a Decimal. at System

What decides Nan and Infinity in java division operations

痴心易碎 提交于 2019-12-05 08:39:44
Output of the below code confusing me. Why NaN sometimes and Infinity other times ? public static void main (String[] args) { double a = 0.0; double b = 1.0; int c = 0; System.out.println(a/0.0); System.out.println(a/0); System.out.println(b/0.0); System.out.println(b/0); System.out.println(c/0.0); System.out.println(c/0); } Outputs is: NaN NaN Infinity Infinity NaN Exception in thread "main" java.lang.ArithmeticException: / by zero What is the deciding factor here ? This is because of The IEEE Standard for Floating-Point Arithmetic (IEEE 754) which is a technical standard for floating-point

How to use division in JavaScript

混江龙づ霸主 提交于 2019-12-05 08:21:07
问题 I want to divide a number in JavaScript and it would return a decimal value. For example: 737/1070 - I want JavaScript to return 0.68 ; however it keeps rounding it off and return it as 0 . How do I set it to return me either two decimals place or the full results? 回答1: Make one of those numbers a float. 737/parseFloat(1070) or a bit faster: 737*1.0/1070 convert to 2 decimal places Math.round(737 * 100.0 / 1070) / 100 回答2: (737/1070).toFixed(2); rounds the result to 2 decimals and returns it

integer division properties

风格不统一 提交于 2019-12-05 05:21:00
does the following integer arithmetic property hold? (m/n)/l == m/(n*l) At first I thought I knew answer (does not hold), but now am not sure. Does it hold for all numbers or only for certain conditions, i.e. n > l ? the question pertains to computer arithmetic, namely q = n/m, q*m != n , ignoring overflow. Case1 assume m = kn+b (b<n), left = (m/n)/l = ((kn+b)/n)/l = (k+b/n)/l = k/l (b/n=0, because b<n) right = (kn+b)/(n*l) = k/l + b/(n*l) = k/l (b/(n*l)=0, because b<n) => left = right Case2 assume m = kn, left = (m/n)/l = (kn/n)/l = k/l right = kn/(n*l) = k/l => left = right So, (m/n)/l == m/