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Aug 31, 2020joshwrou
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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;
}

UNT CSCE 1040 Goat Program

Nov 18, 2022AustinLeath

0 likes • 1 view

#include "goat.h" //include goat.h
void Goat::setBreed(string breed) {
this->breed = breed;
}
void Goat::setWeight(float weight) {
this->weight = weight;
}
void Goat::setName(string name) {
this->name = name;
}
void Goat::setGender(char gender) {
this->gender = gender;
}
void Goat::setSpayed(bool goatIsSpayed) {
this->goatIsSpayed = goatIsSpayed;
}
void Goat::setRegistrationID(string registrationID) {
this->registrationID = registrationID;
}
void Goat::setColor(string color) {
this->color = color;
}
void Goat::setOtherComments(string otherComments) {
this->otherComments = otherComments;
}
string Goat::getBreed() {
return breed;
}
float Goat::getWeight() {
return weight;
}
string Goat::getName() {
return name;
}
char Goat::getGender() {
return gender;
}
bool Goat::getSpayed() {
return goatIsSpayed;
}
string Goat::getRegistrationID() {
return registrationID;
}
string Goat::getColor() {
return color;
}
string Goat::getOtherComments() {
return otherComments;
}
Goat::Goat() {
breed = "";
weight = 0.0;
name = "";
gender = '\0';
goatIsSpayed = false;
registrationID = "";
color = "";
otherComments = "";
}
Goat::Goat(string goatBreed, float goatWeight, string goatName, char goatGender, bool goatSpayedStatus, string goatRegistrationID, string goatColor, string goatOtherComments) {
breed = goatBreed;
weight = goatWeight;
name = goatName;
gender = goatGender;
goatIsSpayed = goatSpayedStatus;
registrationID = goatRegistrationID;
color = goatColor;
otherComments = goatOtherComments;
}
Goat::~Goat() {
cout << "goat destroyed" << endl;
}
void Goat::printinfo() {
cout << "Breed: " << breed << endl << "weight: " << weight << endl << "Name: " << name << endl << "Gender: " << gender << endl << "is Spayed: ";
if(goatIsSpayed) { //here I do a logical test on boolean goatIsSpayed. if true cout << true else cout << false
cout << "True";
} else {
cout << "False";
}
cout << endl << "Registration ID: " << registrationID << endl << "Color Description: " << color << endl << "Other Comments: " << otherComments << endl << endl;
}

Daily: Find missing array value

Aug 5, 2023usama

1 like • 5 views

/*
Good morning! Here's your coding interview problem for today.
This problem was asked by Stripe.
Given an array of integers, find the first missing positive integer in linear time and constant space. In other words, find the lowest positive integer that does not exist in the array. The array can contain duplicates and negative numbers as well.
For example, the input [3, 4, -1, 1] should give 2. The input [1, 2, 0] should give 3.
You can modify the input array in-place.
*/
#include <iostream>
using namespace std;
int calcMissing(int* input, int size)
{
int sum = 0;
int n = 1; //add one to account for missing value
for(int i = 0; i < size; i++)
{
if(input[i] > 0)
{
sum += input[i];
n++;
}
}
//If no numbers higher than 0, answer is 1
if(sum == 0)
return 1;
return (n*(n+1)/2) - sum; //Formula is expectedSum - actualSum
/* expectedSum = n*(n+1)/2, the formula for sum(1, n) */
}
int main()
{
cout << calcMissing(new int[4]{3, 4, -1, 1}, 4) << endl;
cout << calcMissing(new int[3]{1, 2, 0}, 3) << endl;
//No positive numbers
cout << calcMissing(new int[1]{0}, 1) << endl;
}

Infection Simulation

Nov 18, 2022AustinLeath

0 likes • 2 views

/*
this program will simulate the spreading of a disease through a
grid of people, starting from a user-defined person. It will count
the number of turns taken before everyone on the grid is immunized
to the disease after having caught it once.
This program will user the SIR model (Susceptible, Infectious, Recovered)
and cellular automata to simulate the people in the grid.
*/
#include <iostream>
using namespace std;
/* Any and all global variables */
const int SIZE = 8; //Size of the square person array
/* Any and all functions */
void gridDefaultify(char[][SIZE], int);
//Purpose: Sets each item in the person array to 's'
//Parameters: A square, two-dimensional array
// The size of that array's bounds
void gridDisplay(char[][SIZE], int);
//Purpose: Formats and prints the information in the person grid
//Parameters: A square, two-dimensional array
// The value of the current day
void nextTurn(char[][SIZE], char[][SIZE], int&);
//Purpose: Updates the grid of people, and the current day
//Parameters: Two square, two-dimensional arrays
// A reference to the current day (so that it can be updated)
int countInfected(char[][SIZE], int);
//Purpose: Counts the number of infectious people on the grid
//Parameters: A square, two-dimensional array
// The size of that array's bounds
int main(){
int currentDay = 0; //Infection begins on day 0, and ends one day after the last person is Recovered
char gridCurrent[SIZE][SIZE]; //Grid of all people
char gridUpdate[SIZE][SIZE]; //Where the user chooses to start the infection
int xToInfect;
int yToInfect; //Set of coordinates for the initial infection position, given by user
//Initializes the grids to all 's'
gridDefaultify(gridCurrent, SIZE);
gridDefaultify(gridUpdate, SIZE);
//The below block gets the initial infection coordinates from the user
cout << "Please enter a location to infect: ";
while(true){
cin >> xToInfect >> yToInfect;
xToInfect--;
yToInfect--;
if(xToInfect < 0 || yToInfect < 0 || xToInfect >= SIZE || yToInfect >= SIZE){
cout << "Those coordinates are outside the bounds of this region." << endl;
cout << "Please enter another location to infect: ";
continue;
} else {
gridCurrent[xToInfect][yToInfect] = 'i';
break;
}
}
//Displays the initial state of the grid
gridDisplay(gridCurrent, currentDay);
//The below block will display and update the grid until the infection is done.
while(true){
nextTurn(gridCurrent, gridUpdate, currentDay);
gridDisplay(gridCurrent, currentDay);
if(countInfected(gridCurrent, SIZE) == 0) break; //Once there are no more infected, the game is done
}
//Displays the number of days taken for the infection to end
cout << "It took " << currentDay + 1 << " days for the outbreak to end";
cout << endl;
return 0;
}
void gridDefaultify(char arr[][SIZE], int arrSize){
for(int x = 0; x < arrSize; x++){
for(int y = 0; y < arrSize; y++){
arr[x][y] = 's'; //Sets all items in the passed-in array to 's'
}
}
return;
}
void gridDisplay(char arr[][SIZE], int day){
cout << "Day " << day << endl; //Prints the current day
for(int x = 0; x < SIZE; x++){
for(int y = 0; y < SIZE; y++){
cout << arr[x][y] <<" "; //Prints the array's contents
}
cout << endl; //Formats with newlines
}
cout << endl; //Some spacing
return;
}
void nextTurn(char today[][SIZE], char update[][SIZE], int& day){
day++; //Updates the day
int xCheck; //X coordinate to be checked
int yCheck; //Y coordinate to be checked
for(int x = 0; x < SIZE; x++){
for(int y = 0; y < SIZE; y++){
//Sets all 'i' to 'r' in the new grid
if(today[x][y] == 'i' || today[x][y] == 'r'){
update[x][y] = 'r'; //Updates all infectious to recovered, and keeps current recovered
}
if(today[x][y] == 's'){ // If the person is susceptible...
for(int xCheck = x-1; xCheck <= x+1; xCheck++){ // Check all x coordinates around the person
for(int yCheck = y-1; yCheck <= y+1; yCheck++){ // Check all y coordinates around the person
if(xCheck == x && yCheck == y){
// Don't check at the person because there is no need to check there
} else {
if(xCheck >= 0 && yCheck >= 0 && xCheck < SIZE && yCheck < SIZE){ // Make sure the checked coordinates are in bounds
if(today[xCheck][yCheck] == 'i'){ //Is the person at the checked coordinates infected?
update[x][y] = 'i'; //If so, update the 's' to 'i' in the new grid
}
}
}
}
}
}
}
}
for(int x = 0; x < SIZE; x++){
for(int y = 0; y < SIZE; y++){
today[x][y] = update[x][y]; //Updates today's grid with the new values
}
}
}
int countInfected(char arr[][SIZE], int arrSize){
int count = 0;
for(int x = 0; x < arrSize; x++){
for(int y = 0; y < arrSize; y++){
if(arr[x][y] == 'i') count++; //Increments count for each infected person in the grid
}
}
return count;
}

SAM 5 words with bitmaps

Oct 23, 2022LeifMessinger

0 likes • 1 view

//Leif Messinger
//Finds all sets of 5 5 letter words that don't have duplicate letters in either themselves or each other.
//First it reads the words in and puts them in groups of their bitmasks
//After that, we recurse on each group. Before doing that, we remove the group from the set of other groups to check it against.
#include <cstdio> //getchar, printf
#include <cassert> //assert
#include <vector>
#include <set>
#include <algorithm> //std::copy_if
#include <iterator> //std::back_inserter
#define CHECK_FOR_CRLF true
#define MIN_WORDS 5
#define MAX_WORDS 5
#define WORD_TOO_LONG(len) (len != 5)
const unsigned int charToBitmask(const char bruh){
assert(bruh >= 'a' && bruh <= 'z');
return (1 << (bruh - 'a'));
}
void printBitmask(unsigned int bitmask){
char start = 'a';
while(bitmask != 0){
if(bitmask & 1){
putchar(start);
}
bitmask >>= 1;
++start;
}
}
//Pointer needs to be deleted
const std::set<unsigned int>* getBitmasks(){
std::set<unsigned int>* bitmasksPointer = new std::set<unsigned int>;
std::set<unsigned int>& bitmasks = (*bitmasksPointer);
unsigned int bitmask = 0;
unsigned int wordLength = 0;
bool duplicateLetters = false;
for(char c = getchar(); c >= 0; c = getchar()){
if(CHECK_FOR_CRLF && c == '\r'){
continue;
}
if(c == '\n'){
if(!(WORD_TOO_LONG(wordLength) || duplicateLetters)) bitmasks.insert(bitmask);
bitmask = 0;
wordLength = 0;
duplicateLetters = false;
continue;
}
if((bitmask & charToBitmask(c)) != 0) duplicateLetters = true;
bitmask |= charToBitmask(c);
++wordLength;
}
return bitmasksPointer;
}
void printBitmasks(const std::vector<unsigned int>& bitmasks){
for(unsigned int bruh : bitmasks){
printBitmask(bruh);
putchar(','); putchar(' ');
}
puts("");
}
//Just to be clear, when I mean "word", I mean a group of words with the same letters.
void recurse(std::vector<unsigned int>& oldBitmasks, std::vector<unsigned int> history, const unsigned int currentBitmask){
//If there's not enough words left
if(oldBitmasks.size() + (-(history.size())) + (-MIN_WORDS) <= 0){
//If there's enough words
if(history.size() >= MIN_WORDS){
//Print the list
printBitmasks(history);
}
return;
//To make it faster, we can stop it after 5 words too
}else if(history.size() >= MAX_WORDS){
//Print the list
printBitmasks(history);
return;
}
//Thin out the array with only stuff that matches the currentBitmask.
std::vector<unsigned int> newBitmasks;
std::copy_if(oldBitmasks.begin(), oldBitmasks.end(), std::back_inserter(newBitmasks), [&currentBitmask](unsigned int bruh){
return (bruh & currentBitmask) == 0;
});
while(newBitmasks.size() > 0){
//I know this modifies 'oldBitmasks' too. It's intentional.
//This makes it so that the word is never involved in any of the child serches or any of the later searches in this while loop.
const unsigned int word = newBitmasks.back(); newBitmasks.pop_back();
std::vector<unsigned int> newHistory = history;
newHistory.push_back(word);
recurse(newBitmasks, newHistory, currentBitmask | word);
}
}
int main(){
const std::set<unsigned int>* bitmasksSet = getBitmasks();
std::vector<unsigned int> bitmasks(bitmasksSet->begin(), bitmasksSet->end());
delete bitmasksSet;
recurse(bitmasks, std::vector<unsigned int>(), 0);
return 0;
}

CSCE 1040 Lab 9

Nov 18, 2022AustinLeath

0 likes • 2 views

#include <iostream>
#include "PlaylistNode.h"
using namespace std;
void PrintMenu(string title);
int main() {
string plTitle;
cout << "Enter playlist's title:" << endl;
getline(cin, plTitle);
PrintMenu(plTitle);
return 0;
}
void PrintMenu(string title) {
Playlist list;
string id;
string sname;
string aname;
int length;
int oldPos;
int newPos;
char choice;
while(true) {
cout << endl << title << " PLAYLIST MENU" << endl;
cout << "a - Add song" << endl;
cout << "d - Remove song" << endl;
cout << "c - Change position of song" << endl;
cout << "s - Output songs by specific artist" << endl;
cout << "t - Output total time of playlist (in seconds)" << endl;
cout << "o - Output full playlist" << endl;
cout << "q - Quit" << endl << endl;
cout << "Choose an option:" << endl;
cin >> choice;
cin.ignore();
if (choice == 'q') {
exit(1);
}
else if (choice == 'a') {
cout << "\nADD SONG" << endl;
cout << "Enter song's unique ID: ";
cin >> id;
cin.ignore();
cout << "Enter song's name: ";
getline(cin,sname);
cout << "Enter artist's name: ";
getline(cin,aname);
cout << "Enter song's length (in seconds): ";
cin >> length;
list.AddSong(id, sname, aname, length);
}
else if (choice == 'd') {
cout << "\nREMOVE SONG" << endl;
cout << "Enter song's unique ID: ";
cin >> id;
list.RemoveSong(id);
}
else if (choice == 'c') {
cout << "\nCHANGE POSITION OF SONG" << endl;
cout << "Enter song's current position: ";
cin >> oldPos;
cout << "Enter new position for song: ";
cin >> newPos;
list.ChangePosition(oldPos, newPos);
}
else if (choice == 's') {
cout << "\nOUTPUT SONGS BY SPECIFIC ARTIST" << endl;
cout << "Enter artist's name: ";
getline(cin, aname);
list.SongsByArtist(aname);
}
else if (choice == 't') {
cout << "\nOUTPUT TOTAL TIME OF PLAYLIST (IN SECONDS)" << endl;
cout << "Total time: " << list.TotalTime() << " seconds" << endl;
}
else if (choice == 'o') {
cout << endl << title << " - OUTPUT FULL PLAYLIST" << endl;
list.PrintList();
}
else {
cout << "Invalid menu choice! Please try again." << endl;
}
}
}