All Questions
Tagged with c# mathematics
51
questions
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
<...
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 ...
1
vote
2
answers
968
views
Find coprime numbers less than n
I get the coprime numbers less than n with the following algorithm:
...
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 ...
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 ...
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 ...
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 =...
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
...
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 ...
2
votes
2
answers
672
views
Convert a double to a string containing rational and surd
First off, code:
...
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 ...
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 ...
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 ...
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}+ \...