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#include "myfloat_red.h"
// Number of numbers
#define NN 100
#define PRINT_PRECISION 10
#define NEXT_OPG(c) Serial.print("\nOpgave "); Serial.println(c++);
#define AND_OPG(c) Serial.print("and "); Serial.println(c++);
unsigned int opg_count = 1;
void printmydoubarr(myfloat_type *arr, size_t len) {
Serial.print("[ ");
for(size_t i = 0; i < len; i++) {
Serial.print(myfloat2double( &arr[i] ), PRINT_PRECISION);
Serial.print(" ");
}
Serial.println("]");
}
void printarr(double *arr, size_t len) {
Serial.print("[ ");
for(size_t i = 0; i < len; i++) {
Serial.print(arr[i], PRINT_PRECISION);
Serial.print(" ");
}
Serial.println("]");
}
unsigned long factorial(unsigned int n) {
unsigned long res = 1;
for(unsigned int i = 2; i <= n; i++) {
res *= i;
}
return res;
}
double sineTayler(double x, unsigned int n) {
double sum = 0;
for(unsigned int i = 0; i <= n; i++) {
sum += ((double)pow(-1, i) / (double)factorial(2 * i + 1)) * (double)pow(x, 2 * i + 1);
}
return sum;
}
#define TAU 1.57079632679
// After some trial and error the best TAYLORN was 2
#define TAYLORN 2
double sine(double x) {
// Works by finding value in specific -pi/2 to pi/2 period.
int period = x / TAU;
// One cycle of sin takes 4 periods.
// If 0 just return the sine approx x
// If 1 do negative sine approx on x - TAU
// If 2 do negative sine approx x
// If 3 do sine approx on period x - TAU
x = abs(x - TAU*period);
double res = 12;
switch( abs(period % 4) ) {
case 0:
res = sineTayler(x, TAYLORN);
break;
case 1:
res = -sineTayler(x - TAU, TAYLORN);
break;
case 2:
res = -sineTayler(x, TAYLORN);
break;
case 3:
res = sineTayler(x - TAU, TAYLORN);
break;
}
// Remember to multiply with sign
int sign = period < 0 ? -1 : 1;
// Should never return because all cases are handled
return res * sign;
}
void mean_rel_error(double *da, myfloat_type *mda, size_t len, double *sign) {
// Calculate and print the relative error using the formula
// X - x
// ----- Where x is the calculated value and X is the real value( As real as double gets )
// X
double errorsum = 0;
Serial.print("Rel Err : [ ");
for(size_t i = 0; i < len; i++) {
//Serial.println(errorsum, PRINT_PRECISION);
// Make space for sign
if( sign[i] < 0 ) {
Serial.print(" ");
}
// Handle devide by 0
double error = da[i] ? abs(da[i] - myfloat2double(&mda[i])) / abs(da[i]) : 0;
Serial.print(error, PRINT_PRECISION);
Serial.print(" ");
// Save sum for mean
errorsum += error;
}
Serial.println("]");
// Calculate mean
double mean = errorsum / len;
Serial.print("Mean Err: "); Serial.println(mean, PRINT_PRECISION);
}
void setup() {
Serial.begin(115200);
NEXT_OPG(opg_count);
// OPG1. Create some doubles
double da[NN];
for(int i = 0; i < NN; i++) {
da[i] = ((double)random(-5000, 5000)) / 1000.0;
}
Serial.print("Original: "); printarr(da, NN);
NEXT_OPG(opg_count);
// OPG2. Convert to mda
myfloat_type mda[NN];
for(int i = 0; i < NN; i++) {
doub2mydouble(da[i], &mda[i]);
}
Serial.print("Mydoub : "); printmydoubarr(mda, NN);
NEXT_OPG(opg_count);
// OPG3. Calculate the mean relative error
mean_rel_error(da, mda, NN, da);
{
NEXT_OPG(opg_count);
// OPG4. Compute some stuff
double da2[NN];
for(int i = 0; i < NN; i++) {
da2[i] = da[i] * da[i];
}
Serial.print("Orig pow: "); printarr(da2, NN);
NEXT_OPG(opg_count);
// OPG5.
myfloat_type mda2[NN];
for(int i = 0; i < NN; i++) {
// This thing sometimes does weird stuff -4.06*(-4.06) -> -16.00
mult_float(&mda[i], &mda[i], &mda2[i]);
}
Serial.print("Mda pow: "); printmydoubarr(mda2, NN);
NEXT_OPG(opg_count);
// OPG6. Doing the mean error thing
mean_rel_error(da2, mda2, NN, da);
}
{
// OPG7. Measure execution time
NEXT_OPG(opg_count);
double a = da[1];
unsigned long begin = micros();
for(int i = 1; i < NN; i++) {
a *= da[i];
}
unsigned long time1 = micros() - begin;
Serial.print("Exe time: "); Serial.println(time1);
Serial.print("a : "); Serial.println(a);
NEXT_OPG(opg_count);
// Convert to myfloat
myfloat_type f1;
doub2mydouble(a, &f1);
Serial.print("f1 : "); Serial.println(myfloat2double(&f1));
NEXT_OPG(opg_count);
// OPG8-9.
begin = micros();
for(int i = 0; i < NN; i++) {
// Multiply
myfloat_type f;
mult_float(&f1, &mda[i], &f);
// Copy back
memcpy(&f1, &f, sizeof(myfloat_type));
}
unsigned long time2 = micros() - begin;
Serial.print("Exe time: "); Serial.println(time2);
Serial.print("f1 : "); Serial.println(myfloat2double(&f1));
Serial.println("Overflow");
NEXT_OPG(opg_count);
// OPG10. Difference relative to biggest result
unsigned long absdiff = abs( time1 - time2 );
Serial.print("Abs diff: "); Serial.println(absdiff);
double reldiff = (double)absdiff / max(abs(time1), abs(time2));
Serial.print("Rel diff: "); Serial.println(reldiff);
}
NEXT_OPG(opg_count);
// OPG11. Impl sine
// Hardest value should be TAU as it's the furthest from center.
unsigned long begin = micros();
double res = sine(TAU);
unsigned long time1 = micros() - begin;
Serial.print("own sin : "); Serial.println(res, PRINT_PRECISION);
begin = micros();
double correct = sin(TAU);
unsigned long time2 = micros() - begin;
Serial.print("ard sin : "); Serial.println(correct, PRINT_PRECISION);
double error = correct ? abs(correct - res) / abs(correct) : 0;
Serial.print("rel err : "); Serial.println(error, PRINT_PRECISION);
Serial.print("\nown time: "); Serial.println(time1);
Serial.print("ard time: "); Serial.println(time2);
}
void loop() {
}
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