## Division of two instructions with the number returns zero

I am new to SQL (using SQLiteStudio) and am trying to work with some of the aggregate functions. I want to find the proportion of a subset of my data where mass of individuals is less than 575, but the query keeps returning zero: SELECT A/B*100 FROM

## Basic arithmetic in a function does not work

I have a PHP function I'm using to count files within a directory. function getFileCount(\$path) { \$size = 0; \$ignore = array('.','..','cgi-bin','.DS_Store'); \$files = scandir(\$path); foreach(\$files as \$t) { if(in_array(\$t, \$ignore)) continue; if (is_

## How can I divide a signed integer using only binary operators?

I can only use ! ~ & ^ | + << >> I am writing this in C. I am trying to divide a number x by 2^n. So i thought if I shift x >> n that would work, but it does not work with odd negative integers. It originally looked like this: int dl

## Effective algorithm to determine if a very large number is divisible by 7

So this was a question on one of the challenges I came across in an online competition, a few days ago. Question: Accept two inputs. A big number of N digits, The number of questions Q to be asked. In each of the question, you have to find if the num

## Two dividing vectors

I have first vector, example: x=1:10 and second with prime numbers, example y=c(2,3,5,7) And I want sort vector x: divisible by 2, divisible by 3, etc. So, The output would look like this: 2 4 6 8 10 3 9 5 7Using apply loop and mod: unique(unlist(sap

## How is the scale defined when decimal and bigint are divided?

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

## Expensive floating division

On modern processors, float division is a good order of magnitude slower than float multiplication (when measured by reciprocal throughput). I'm wondering if there are any algorithms out there for computating a fast approximation to x/y, given certai

## Reduce the values ​​of the large data frame to smaller data frame frames when the dimensions are not divisible

I have two data frames. One is ~133 rows and one is ~4337 rows. They each have two columns containing the same type of information. Sun elevation in the first column and Radiance in the second column. I would like to reduce the number of rows of the

## Select the arithmetic query calculation

I would like to make some basic calculations with a select query. I have a table called Distances, and there is an attribute saved distance. I would like to calculate distance of Customer1/Sum of distances of Customer1, Customer2 and Customer3. Is th

## How to change the product weight from grams to Kg with MySql?

I have 610 products with weights measured in Grams, in a database of over 2000 products. I can find those products with this search SELECT * FROM `jos_vm_product` WHERE `product_weight_uom` LIKE 'grams' I would like to change the weight to Kg, which

## How to calculate a check digit for a large number in R?

I must add a 2-digit check (remaining of division by 97) to numbers such as 52/200005/0001 (slashes must be ignored). My code is the following, but it fails because of too big number: AppendCheckDigits <- function (x) { stopifnot(is.character(x) &

## C calculation and casting of mixed types

I want to calculate an average value on my microcontroller with this formula: uint16_t uAverage; uint64_t counter; uint16_t u; uAverage = uAverage * (1 + 1 / counter) + u / counter; But I had problems with those calculations in the past and this is a

## Why does Python 3.4 give the wrong answer for the division of large numbers, and how can I test divisibility?

In my program, I'm using division to test if the result is an integer, I'm testing divisibility. However, I'm getting wrong answers. Here is an example: print(int(724815896270884803/61)) gives 11882227807719424. print(724815896270884803//61) gives th

## Division c does not give expected value

When doing a division im getting a rounded answer? double div; div = 25/8; printf("%lf",div); When i do this prints out 3.0000 why dont i get 3.125?Because you are doing an integer division, try with: div = 25.0/8; or div = (double)25/8; Typing

## Dividing two large long ones while maintaining accuracy and precision

I have two large long values, e.g. long a = 106951484895 and long b = 47666297253. I want to divide one by the other, while still retaining precision and accuracy. a / b gives just 2, which is neither precise nor accurate. (double)a / b returns 2.243

## Verilog Sequential Division

Can anyone tell me what should be the width of dividend and divisor in sequential division. As of now i have designed the divider which has WIDTH_DIVID=2*wIDTH_DIVIS. If i voilate this relation my division fails. Can anyone help me with this My veril

## Division and rest in Prolog

Trying to figure out how to write a recursive predicate divide_by(X, D, I, R) that takes as input a positive integer X and a divisor D, and returns the answer as the whole number part I and the remainder part R, however, I can't seem to get my head a

## Division into VHDL (int / float)

I want to divide two numbers(16-bit binary) in VHDL in 1 cycle (combinational circuit). Numerator is an integer. Denominator is a float. Result should be float. What algorithm do i use to perform the division. Please helpHere is an entity that does w

## Java round up the results of a division when it should not be

So I have some code for scaling graphics to the size of a users screen by dividing the size of an 'Ideal' screen by the size of the users screen. Hers is a code snippet of what I'm doing: public void setScaleFactor(GameContainer ui) { scaleFactorWidt

## How to divide in decimals and not get zero in Java?

This question already has an answer here: How to make the division of 2 ints produce a float instead of another int? 9 answers double[] arrayName = new double; arrayName = (14/49)*100; Trying to get percentage of two numbers, 14 / 49, and add

## Java: How to perform an integer division rounded to -Infinity rather than 0?

(note: not the same as this other question since the OP never explicitly specified rounding towards 0 or -Infinity) JLS 15.17.2 says that integer division rounds towards zero. If I want floor()-like behavior for positive divisors (I don't care about

## Simple Modulo Operations

So I am learning C++, and in one of the books I'm reading, there is an example for finding GCF (greatest common factor). The function is as follows: int gcf(int a, int b) { if(b == 0) { return a; } else { return gcf(b, a%b); } } What I don't understa

## Find consecutive 00s and 11s in a vector

I have a vector a = 1111000011100001110000100100 and I have to compute two values based on it: p00 and p11. p00 is the number of times 00 is occurring in the vector, divided by the total number of zeros. For example, in the above code then number of

## Double precision in C - print 50 significant digits give inaccurate values

I'm doing an integration program with Riemann sums for my Calculus class. I've decided to use C when computing my integrals, and I noticed a huge error in my program that derives from this problem. #include <stdio.h> #include <stdlib.h> #inclu

## Division at Haskell

I'm making a function in Haskell that halves only the evens in a list and I am experiencing a problem. When I run the complier it complains that you can't perform division of an int and that I need a fractional int type declaration. I have tried chan

## Difference between & ldquo; Math.DivRem & quot; and% operator?

What is the difference between System.Math.DivRem() and the % operator?% gives you the remainder of a division and discards the quotient altogether, while DivRem() calculates and returns both the quotient and the remainder. If you're only concerned a

## PHP - adjust the time () to be divisible by 5

I'm using PHP's time() to set two dates (default values for two input fields): a start date, which should be the current time: date('m/d/Y H:i', time()); a end date, which should be the current time + 2 hours: date('m/d/Y H:i', time() + 60*60*2); How

## Exceeding Exception When Splitting Two Decimal Places in .NET

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 = -

## insert & hellip; select with the division operator in selection errors?

CREATE TABLE IF NOT EXISTS XY ( x INT NOT NULL , y FLOAT NULL , PRIMARY KEY(x) ) INSERT INTO XY (x,y) (select 1 as x ,(1/7) as y); errors with Error code 1064, SQL state 42000: You have an error in your SQL syntax; check the manual that corresponds t

## Division Zero does not throw an exception in Nunit

Running the following C# code through NUnit yields Test.ControllerTest.TestSanity: Expected: `<System.DivideByZeroException>` But was: null So either no DivideByZeroException is thrown, or NUnit does not catch it. Similar to this question, but the a