FUNCTION_BLOCK disease

VAR_INPUT
    temperature: REAL;
    sneezing: REAL;
    cough: REAL;
    sore_throat: REAL;
    heavy_breathing: REAL;
    headache: REAL;
    chest_pain: REAL;
    runny_nose: REAL;
    bloody_cough: REAL;
END_VAR

VAR_OUTPUT
    decision: REAL;
END_VAR

FUZZIFY temperature
    TERM low := TRAPE 0 28 32 36;
    TERM normal := TRAPE 35.8 36.5 36.9 37;
    TERM high := TRAPE 36.5 40 40 43.5;
END_FUZZIFY

FUZZIFY sneezing
    TERM barely := (0, 1.0) (3, 0.0);
    TERM little := (2, 0.0) (3, 1.0) (4, 1.0) (5, 0.0);
    TERM often := (4, 0.0) (7, 1.0) (8, 1.0) (10, 0.0);
END_FUZZIFY

FUZZIFY cough
    TERM little := (2, 0.0) (3, 1.0) (4, 1.0) (5, 0.0);
    TERM often := (4, 0.0) (6, 1.0) (7, 1.0) (8, 0.0);
    TERM all_the_time := (7, 0.0) (8, 1.0) (9, 1.0) (10, 0.0);
END_FUZZIFY

FUZZIFY sore_throat
    TERM not_at_all := TRAPE 0 2 3 4;
    TERM little := TRAPE 3 4 6 7;
    TERM very := TRAPE 6 7 9 10;
END_FUZZIFY

FUZZIFY heavy_breathing
    TERM not_at_all := GBELL 2 3 2;
    TERM slight := GBELL 2 3 5;
    TERM very := GBELL 2 3 8;
END_FUZZIFY

FUZZIFY headache
    TERM not_at_all := TRIAN 0 2.5 5;
    TERM little := TRIAN 2.5 5 7.5;
    TERM very := TRIAN 6 9 10;
END_FUZZIFY

FUZZIFY chest_pain
    TERM not_at_all := TRIAN 0 2.5 5;
    TERM little := TRIAN 2.5 5 7.5;
    TERM very := TRIAN 6 9 10;
END_FUZZIFY

FUZZIFY runny_nose
    TERM not_at_all := TRAPE 0 1 2 3;
    TERM little := TRAPE 2 3 4 5;
    TERM often := TRAPE 4 5 6 7;
    TERM constant := TRAPE 6 7 8 10;
END_FUZZIFY

FUZZIFY bloody_cough
    TERM not_at_all := TRIAN 0 2.5 5;
    TERM little := TRIAN 2.5 5 7.5;
    TERM very := TRIAN 6 9 10;
END_FUZZIFY

DEFUZZIFY decision
    TERM cold := GBELL 2 2 2;
    TERM flu := GBELL 2 2 5;
    TERM allergy := GBELL 2 2 8;
    TERM bronhitis := GBELL 2 2 11;
    TERM pneumonia := GBELL 2 2 14;
    TERM lung_cancer := GBELL 2 2 17;
    TERM tuberculosis := GBELL 2 2 20;
    TERM laryngitis := GBELL 2 2 23;
   	TERM heartAttack := GBELL 2 2 26;
   	TERM outOfShape := GBELL 2 2 29;
   	    // Use 'Center Of Gravity' defuzzification method
    METHOD : COG;
    // Default value is 0 (if no rule activates defuzzifier)
    DEFAULT := 0;
END_DEFUZZIFY


RULEBLOCK No1
	AND : MIN;	// Use 'min' for 'and'
	ACT : MIN;	// Use 'min' activation method
	ACCU : MAX;	// Use 'max' accumulation method

	RULE 1 : IF temperature IS low AND runny_nose IS often OR runny_nose IS constant AND sneezing IS often THEN decision IS cold;
	RULE 2 : IF heavy_breathing IS very AND bloody_cough IS very AND chest_pain IS very THEN decision IS lung_cancer;
	RULE 3 : IF bloody_cough IS little AND chest_pain IS little AND temperature IS high THEN decision IS tuberculosis;
	RULE 4 : IF runny_nose IS constant AND temperature IS normal AND sneezing IS often THEN decision IS allergy;
	RULE 5 : IF sore_throat IS very AND cough IS often AND temperature IS high THEN decision IS laryngitis;
	RULE 6 : IF temperature IS high AND heavy_breathing IS very AND chest_pain IS little THEN decision IS pneumonia;
	RULE 7 : IF chest_pain IS very AND headache IS very THEN decision IS heartAttack;
	RULE 8 : IF temperature IS high AND runny_nose IS often OR runny_nose IS constant AND sneezing IS often OR sneezing IS little THEN decision IS cold;
	RULE 9: IF cough IS often OR bloody_cough IS little AND runny_nose IS not_at_all THEN decision IS bronhitis;
	RULE 10: IF temperature IS normal AND heavy_breathing IS very AND chest_pain IS very THEN decision IS outOfShape;
END_RULEBLOCK

END_FUNCTION_BLOCK