All Questions
Tagged with c# mathematics
51
questions
5
votes
2
answers
264
views
C# console app that computes the Jaccard Index
So I wrote a basic C# console application that computes the Jaccard Index. This has its applications in cybersecurity and machine learning. Given two sets X and Y, the basic formula is:
$$ J(X, Y) = \...
- 183
1
vote
0
answers
147
views
Interleave Bits Generically
This commonly referenced "bit twiddling" site has an interesting algorithm for interleaving the bits of two 32-bit integers. Here is my attempt at completely generalizing the algorithm using ...
- 1,940
2
votes
2
answers
133
views
generate prime factors via wheel factorization
I want to factor random values of n that range from uint.MinValue to uint.MaxValue as ...
- 1,940
4
votes
2
answers
204
views
32-bit deterministic Miller-Rabin primality test
Are there any ways in which this code could be improved? I'm particularly interested in the ModularExponentiation function as it is the primary bottleneck during ...
- 1,940
5
votes
4
answers
4k
views
Dividing two numbers then handle the divide by zero exception with try/catch
I am new to coding, I hope you can help me to improve my code :)
First of all: The code works correctly.
...
- 53
3
votes
1
answer
337
views
Generic Integer Square Root
I have implemented an integer square root function that is branch-free and runs in constant time, using the first variant found in this answer as a base. All possible values for the types ...
- 1,940
2
votes
1
answer
268
views
Compute the derivative of a function
1.11 Arranging the derivative of a function
The derivative of any function f (x) at x0 can be estimated according to the following formula:
Write a program that prints three columns of ...
- 647
3
votes
1
answer
414
views
Rock Paper Scissors without arrays and if-statements, how to reduce
As working on a little private programming challenge, I tried "Rock Paper Scissors" without arrays or if-statements. It works as intended, though, I am sure this can be done a little bit more ...
- 141
6
votes
1
answer
747
views
C# random math questions project
I made a C# console math project where the user answers addition, subtraction, multiplication, division, power or square-root questions based on the difficulty they choose!
However, I am struggling ...
- 161
2
votes
2
answers
463
views
C# maths quiz with user choosen difficulty-level
I have built a maths project that asks the user an addition, subtraction, multiplication, division, power and square root questions based on the difficulty level they choose!
But I am trying to ...
- 161
6
votes
4
answers
263
views
All your Base - Exercism.io
This is an exercise on the website Exercism. I am self taught trying to learn C# and C++. This is the information from the readme.
Convert a number, represented as a sequence of digits in one base,...
- 620
4
votes
1
answer
524
views
Solving a linear system with two variables
Background:
Equation 1: 2x-y=6
Equation 2: 4x+3y=22
Because 1 is ax-by=c and 2 is dx-ey=f
y=(a * f - c * d) / (a * e - b * d) and x is simply (c - (b * y)) / a)
What I am trying to do:
...
- 41
3
votes
4
answers
8k
views
C# Code to Find all Divisors of an Integer
I made this so I can feed it integers and return an array with all the divisors of that integer. I put checks in in case the integer is less than 2. Order of integers in the array must be smallest ...
- 620
3
votes
2
answers
470
views
Get resulting rectangle from two overlapping rectangles
I have a function that creates a rectangle from two rectangles that overlap, I was wondering if there is a smarter way to do it purely mathematically rather than lots of ...
- 247
3
votes
2
answers
126
views
Project price of publicly traded contract
I have to project the price for a publicly traded contract when the price should be approximately matching the targeted profit or loss. I have written the following code, runs under 0.02ms.. could be ...
- 464
7
votes
3
answers
3k
views
Calculator of combinations without repetition
I am interested to find an absolute value (not an approximation) of "combination without repetition" for given \$n\$ and \$k\$, or \$\binom{n}{k}\$.
The brute force solution would look like this
<...
- 922
8
votes
1
answer
691
views
Lagrange Interpolation over quadrilateral points
I've been working on a program which calculates, given a point and 4 surrounding points, the Lagrange polynomial, in order to interpolate a value. Consider that I'm not a mathematician and I better ...
- 131
1
vote
2
answers
968
views
Find coprime numbers less than n
I get the coprime numbers less than n with the following algorithm:
...
- 119
7
votes
2
answers
2k
views
Class Matrix implementation
Following the 18.06 Linear algebra course, I was curious to reinvent the matrix class and basic functionality, like \$PA=LU \$ decomposition, Gauss elimination, finding inverse matrix etc.
Any ...
- 922
6
votes
4
answers
612
views
Pascal Triangle calculation with BigIntegers
On a well known programming challenges website(CW) there is a Kyu2 eggs height problem that can be solved utilizing a variation of Pascals Triangles properties.
The problem asks to solve ...
- 160
4
votes
1
answer
645
views
Method to return center items in a 2D array
I wish to have code that returns the center items of a 2d grid. Because I need an average value. The code I came up with does what I want (see the unit tests beneath it). But I think the code is ugly ...
- 167
4
votes
1
answer
211
views
Rare binary numbers
Rare numbers are the natural numbers in their binary forms in which there aren't two (or more) ones next to each other. Make a program that will give the N. rare number!
For example:
In case of N =...
- 143
3
votes
5
answers
2k
views
Absolute Values and Fractions
$$
\frac{|x|-|y|}{1+|xy|}
$$
How can I reduce the amount of code without losing quality? What are your tips? Your comments on the structure, logic, in general, everything. How to make the type of ...
-2
votes
3
answers
180
views
Find target sum of 3 from and array
Input is a sorted array and a target sum. Find all sets of 3 unique elements that sum to a target.
Looking for lowest order (big O).
A, B, C are the indexes on the sorted array. A < B < C
...
- 6,016
7
votes
2
answers
861
views
Optimizing special cases of modulo
I have a use case where improvements to the speed of calculating modulo for 64 bit integer dividends makes a significant difference in overall processing time.
The divisor isn't known statically - it ...
- 273
2
votes
2
answers
672
views
8
votes
1
answer
3k
views
Generating Uniformly Distributed Random Numbers
Edit: Dunno what PCG is and don't want to read the paper? Maybe this video of Melissa O'Neill (the author) explaining things will be palatable instead.
Original: I attempted to answer this question ...
- 1,940
10
votes
2
answers
248
views
Resizing a discrete uniform CSRNG distribution
I have a requirement to generate a uniform distribution of cryptographically secure random numbers. To generate these numbers I only know of the ...
- 43.4k
4
votes
2
answers
4k
views
Calculating distance and angle between two points, C# program
I like to think I'm an intermediate programmer, but I learned to code with the Unity engine so I'm still getting used to not using it, and I've never had someone review my code before. I don't know ...
- 43
7
votes
2
answers
182
views
Sum of the reciprocals of whole numbers adding to one
I have written some code which works out which sums of reciprocals of whole numbers sum to one, e.g:
\$\frac 12 +\frac 13 +\frac 16 =1 \$
\$\frac 17 +\frac 18 +\frac 19 + \frac1{10} + \frac1{11}+ \...
- 71