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Egg Problem Template

Jul 10, 2023LeifMessinger
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Audio Frequency Amplitudes

Aug 27, 2021LeifMessinger

0 likes • 1 view

//From https://create.arduino.cc/projecthub/abhilashpatel121/easyfft-fast-fourier-transform-fft-for-arduino-9d2677
#include <cmath>
#include <iostream>
const unsigned char sine_data[] = { //Quarter a sine wave
0,
4, 9, 13, 18, 22, 27, 31, 35, 40, 44,
49, 53, 57, 62, 66, 70, 75, 79, 83, 87,
91, 96, 100, 104, 108, 112, 116, 120, 124, 127,
131, 135, 139, 143, 146, 150, 153, 157, 160, 164,
167, 171, 174, 177, 180, 183, 186, 189, 192, 195, //Paste this at top of program
198, 201, 204, 206, 209, 211, 214, 216, 219, 221,
223, 225, 227, 229, 231, 233, 235, 236, 238, 240,
241, 243, 244, 245, 246, 247, 248, 249, 250, 251,
252, 253, 253, 254, 254, 254, 255, 255, 255, 255
};
float sine(int i){ //Inefficient sine
int j=i;
float out;
while(j < 0) j = j + 360;
while(j > 360) j = j - 360;
if(j > -1 && j < 91) out = sine_data[j];
else if(j > 90 && j < 181) out = sine_data[180 - j];
else if(j > 180 && j < 271) out = -sine_data[j - 180];
else if(j > 270 && j < 361) out = -sine_data[360 - j];
return (out / 255);
}
float cosine(int i){ //Inefficient cosine
int j = i;
float out;
while(j < 0) j = j + 360;
while(j > 360) j = j - 360;
if(j > -1 && j < 91) out = sine_data[90 - j];
else if(j > 90 && j < 181) out = -sine_data[j - 90];
else if(j > 180 && j < 271) out = -sine_data[270 - j];
else if(j > 270 && j < 361) out = sine_data[j - 270];
return (out / 255);
}
//Example data:
//-----------------------------FFT Function----------------------------------------------//
float* FFT(int in[],unsigned int N,float Frequency){ //Result is highest frequencies in order of loudness. Needs to be deleted.
/*
Code to perform FFT on arduino,
setup:
paste sine_data [91] at top of program [global variable], paste FFT function at end of program
Term:
1. in[] : Data array,
2. N : Number of sample (recommended sample size 2,4,8,16,32,64,128...)
3. Frequency: sampling frequency required as input (Hz)
If sample size is not in power of 2 it will be clipped to lower side of number.
i.e, for 150 number of samples, code will consider first 128 sample, remaining sample will be omitted.
For Arduino nano, FFT of more than 128 sample not possible due to mamory limitation (64 recomended)
For higher Number of sample may arise Mamory related issue,
Code by ABHILASH
Documentation:https://www.instructables.com/member/abhilash_patel/instructables/
2/3/2021: change data type of N from float to int for >=256 samples
*/
unsigned int sampleRates[13]={1,2,4,8,16,32,64,128,256,512,1024,2048};
int a = N;
int o;
for(int i=0;i<12;i++){ //Snapping N to a sample rate in sampleRates
if(sampleRates[i]<=a){
o = i;
}
}
int in_ps[sampleRates[o]] = {}; //input for sequencing
float out_r[sampleRates[o]] = {}; //real part of transform
float out_im[sampleRates[o]] = {}; //imaginory part of transform
int x = 0;
int c1;
int f;
for(int b=0;b<o;b++){ // bit reversal
c1 = sampleRates[b];
f = sampleRates[o] / (c1 + c1);
for(int j = 0;j < c1;j++){
x = x + 1;
in_ps[x]=in_ps[j]+f;
}
}
for(int i=0;i<sampleRates[o];i++){ // update input array as per bit reverse order
if(in_ps[i]<a){
out_r[i]=in[in_ps[i]];
}
if(in_ps[i]>a){
out_r[i]=in[in_ps[i]-a];
}
}
int i10,i11,n1;
float e,c,s,tr,ti;
for(int i=0;i<o;i++){ //fft
i10 = sampleRates[i]; // overall values of sine/cosine :
i11 = sampleRates[o] / sampleRates[i+1]; // loop with similar sine cosine:
e = 360 / sampleRates[i+1];
e = 0 - e;
n1 = 0;
for(int j=0;j<i10;j++){
c=cosine(e*j);
s=sine(e*j);
n1=j;
for(int k=0;k<i11;k++){
tr = c*out_r[i10 + n1]-s*out_im[i10 + n1];
ti = s*out_r[i10 + n1]+c*out_im[i10 + n1];
out_r[n1 + i10] = out_r[n1]-tr;
out_r[n1] = out_r[n1]+tr;
out_im[n1 + i10] = out_im[n1]-ti;
out_im[n1] = out_im[n1]+ti;
n1 = n1+i10+i10;
}
}
}
/*
for(int i=0;i<sampleRates[o];i++)
{
std::cout << (out_r[i]);
std::cout << ("\t"); // un comment to print RAW o/p
std::cout << (out_im[i]); std::cout << ("i");
std::cout << std::endl;
}
*/
//---> here onward out_r contains amplitude and our_in conntains frequency (Hz)
for(int i=0;i<sampleRates[o-1];i++){ // getting amplitude from compex number
out_r[i] = sqrt(out_r[i]*out_r[i]+out_im[i]*out_im[i]); // to increase the speed delete sqrt
out_im[i] = i * Frequency / N;
std::cout << (out_im[i]); std::cout << ("Hz");
std::cout << ("\t"); // un comment to print freuency bin
std::cout << (out_r[i]);
std::cout << std::endl;
}
x = 0; // peak detection
for(int i=1;i<sampleRates[o-1]-1;i++){
if(out_r[i]>out_r[i-1] && out_r[i]>out_r[i+1]){
in_ps[x] = i; //in_ps array used for storage of peak number
x = x + 1;
}
}
s = 0;
c = 0;
for(int i=0;i<x;i++){ // re arraange as per magnitude
for(int j=c;j<x;j++){
if(out_r[in_ps[i]]<out_r[in_ps[j]]){
s=in_ps[i];
in_ps[i]=in_ps[j];
in_ps[j]=s;
}
}
c=c+1;
}
float* f_peaks = new float[sampleRates[o]];
for(int i=0;i<5;i++){ // updating f_peak array (global variable)with descending order
f_peaks[i]=out_im[in_ps[i]];
}
return f_peaks;
}
//------------------------------------------------------------------------------------//
//main.cpp
int data[64]={
14, 30, 35, 34, 34, 40, 46, 45, 30, 4, -26, -48, -55, -49, -37,
-28, -24, -22, -13, 6, 32, 55, 65, 57, 38, 17, 1, -6, -11, -19, -34,
-51, -61, -56, -35, -7, 18, 32, 35, 34, 35, 41, 46, 43, 26, -2, -31, -50,
-55, -47, -35, -27, -24, -21, -10, 11, 37, 58, 64, 55, 34, 13, -1, -7
};
int main(){
const unsigned int SAMPLE_RATE = 48*1000; //48khz
auto result = FFT(data,64,SAMPLE_RATE);
std::cout << result[0] << " " << result[1] << " " << result[2] << " " << result[3] << std::endl;
delete[] result;
return 0;
}

minimum matrix values

Nov 18, 2022AustinLeath

0 likes • 4 views

#include <iostream>
using namespace std;
int main() {
const int ROW_SIZE = 2;
const int COLUMN_SIZE = 5; //establish all variables
int matrix[ROW_SIZE][COLUMN_SIZE];
int minVal;
for (int i = 0; i < ROW_SIZE; ++i) // for loop to ask user to enter data.
{
for (int h = 0; h < COLUMN_SIZE; ++h) {
cout << "Enter data for row #" << i + 1 << " and column #" << h + 1 << ": ";
cin >> matrix[i][h];
}
}
cout << "You entered: " << endl;
for (int i = 0; i < ROW_SIZE; ++i) //for statements to output the array neatly
{
for (int h = 0; h < COLUMN_SIZE; ++h) {
cout << matrix[i][h] << "\t";
}
cout << endl;
}
cout << "Minimum for each row is: {";
for (int i = 0; i < ROW_SIZE; i++) //for statements to find the minimum in each row
{
minVal = matrix[i][0];
for (int h = 0; h < COLUMN_SIZE; h++) {
if (matrix[i][h] < minVal) // if matrix[i][h] < minVal -> minVal = matrix[i][h];
{
minVal = matrix[i][h];
}
}
cout << minVal << ", ";
}
cout << "}" << endl;
cout << "Minimum for each column is: {";
for (int i = 0; i < COLUMN_SIZE; i++) //for statements to find the minimum in each column
{
minVal = matrix[0][i];
for (int h = 0; h < ROW_SIZE; h++) {
if (matrix[h][i] < minVal) //replaces minVal with array index for that column that is lowest
{
minVal = matrix[h][i];
}
}
cout << minVal << ", ";
}
cout << "}" << endl;
return 0;
}

sum function

Sep 3, 2023AustinLeath

0 likes • 10 views

#include "stdio.h"
#include <stdlib.h>
int main (int argCount, char** args) {
int a = atoi(args[1]);
int b = atoi(args[2]);
unsigned int sum = 0;
unsigned int p = 1;
for (unsigned int i = 1; i < b; i++) {
p = p * i;
}
// (b!, (1 + b)!, (2 + b)!, ..., (n + b)!)
for (unsigned int i = 0; i < a; i++) {
p = p * (i + b);
sum = sum + p;
}
printf("y: %u\n", sum);
return 0;
}

Stock Options Analyzer

Nov 18, 2022AustinLeath

0 likes • 0 views

#include <iostream>
#include <cmath>
#include <string.h>
using namespace std;
int main() {
string tickerName;
int numOfContracts;
float currentOptionValue;
cout << "Enter a stock ticker: ";
getline(cin, tickerName);
cout << "Enter the current number of " << tickerName << " contracts you are holding: ";
cin >> numOfContracts;
cout << "Enter the current price of the option: ";
cin >> currentOptionValue;
cout << "The value of your " << tickerName << " options are: $" << (currentOptionValue * 100.00) * (numOfContracts);
cout << endl;
return 0;
}

GCD using Stein's Algorithm

Jun 30, 2023Iceman_71

1 like • 7 views

// Iterative C++ program to
// implement Stein's Algorithm
//#include <bits/stdc++.h>
#include <bitset>
using namespace std;
// Function to implement
// Stein's Algorithm
int gcd(int a, int b)
{
/* GCD(0, b) == b; GCD(a, 0) == a,
GCD(0, 0) == 0 */
if (a == 0)
return b;
if (b == 0)
return a;
/*Finding K, where K is the
greatest power of 2
that divides both a and b. */
int k;
for (k = 0; ((a | b) & 1) == 0; ++k)
{
a >>= 1;
b >>= 1;
}
/* Dividing a by 2 until a becomes odd */
while ((a & 1) == 0)
a >>= 1;
/* From here on, 'a' is always odd. */
do
{
/* If b is even, remove all factor of 2 in b */
while ((b & 1) == 0)
b >>= 1;
/* Now a and b are both odd.
Swap if necessary so a <= b,
then set b = b - a (which is even).*/
if (a > b)
swap(a, b); // Swap u and v.
b = (b - a);
} while (b != 0);
/* restore common factors of 2 */
return a << k;
}
// Driver code
int main()
{
int a = 12, b = 780;
printf("Gcd of given numbers is %d\n", gcd(a, b));
return 0;
}

Simple Greedy sort C++

Jun 30, 2023Iceman_71

0 likes • 7 views

#include <iostream>
using namespace std;
int main()
{
int arr[] = {5, 1, 4, 20, 10, 2, 13, 11, 6, 21};
int greed[] = {0, 0, 0, 0};
int k = 0;
int i;
int set_index;
while (k < 4)
{
i = 0;
while (i < 10)
{
if (arr[i] > greed[k])
{
greed[k] = arr[i];
set_index = i;
}
i++;
}
arr[set_index] = 0;
k++;
}
cout << greed[0] << " " << greed[1] << " " << greed[2] << " " << greed[3] << endl;
}