Utilisation de Switch a la place de if else if else (Arduino

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int

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float

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switch

switch

goto

if ... else if ...

#include <stdio.h>

typedef struct _note_t {
    unsigned short min;
    unsigned short max;
    const char * name;
} note_t;

static const note_t NOTES[] = {
    {495, 528, "Do4"},
    {470, 495, "Si3"},
    // ...
};

const char * find_note(double freq) {
    const note_t * note = &(NOTES[0]);
    unsigned num_notes = sizeof(notes) / sizeof(note_t);
    for (unsigned i = 0; i < num_notes; i++, note++) {
        if (note->min <= freq && freq < note->max) {
            return note->name;
        }   
    }                                     
    return NULL;                          
}                                         

int main(){
    double freqs[] = {400, 470, 475, 495, 500, 530};
    unsigned num_freqs = sizeof(freqs) / sizeof(double);
    const double * pfreq = &freqs[0];
    for (unsigned i = 0; i < num_freqs; i++, pfreq++) {
        double freq = *pfreq;
        printf("find_note(%lf) = %s\n", freq, find_note(freq));
    }   
    return 0;               
}

(mando@silk) (~) $ gcc notes.c && ./a.out 
find_note(400.000000) = (null)
find_note(470.000000) = Si3
find_note(475.000000) = Si3
find_note(495.000000) = Do4
find_note(500.000000) = Do4
find_note(530.000000) = (null)

CASEQ

CASLT

CASGT

switch

    // Recherche dans le tableau [0,7] (frequence & nom de la note)
    for (int i = 0 ; i < Tab_Max; ++i)
     {
        // Si la recherche n a pas abouti, on compare
        if ((sensorValue >= Tab_Notes[i]) && (Trouve == 0))  
         {
            Frequence = Tab_Notes[i];
            Note      = Lib_Notes[i];
            Trouve    = 1;
         }
     }
    
    // Si Trouve = 0... (pas abouti)
    // la frequence est plus basse que Do3 ( <264 ), 
    // forcer a Do3 inferieur
    if (Trouve == 0)
    {
        Frequence = Tab_Notes[Tab_Max] - 64;    // frequence = 200
        Note      = "en dessous";
    }