*sorry/pardon for my bad englisch communication/conversation*

that’s an very interesting exercise/question to difference in math. modus or (various) µC-programming modi or logical modus

so i try to explain out of my programmers viewpoint to approach one (of many) possible solution:

**logical task: µC-programming**

int x //variable: -32768…+32767 == „small-integer“ 2 Bytes//

int a_n //listed in table or matrix, /wobei/within/ n == „position number in list“//

cases: //successive read out! - - - cases in CALC: „=IFS()“//

-.1. x == a_n, TRUE ⋎ FALSE (boolean) //== : equal to / ⋎ : logical OR//

-.2. x != a_n, TRUE ⋎ FALSE (boolean) //!= : logical NOT//

-.3. x > a_n, TRUE ⋎ FALSE (boolean) //> : greater than//

-.4. x < a_n, TRUE ⋎ FALSE (boolean) //< : lower than//

-.5. x != int x, ERROR ⋎ NaN //NaN : not a number, but a value how 4.75 decimal//

- break; //do not drive into a infinite loop if fault in all above cases!//

for

a_1 = 682

a_2 = 657

a_5 = 636 //switched with another position//

a_4 = 645

a_3 = 654 //switched with another position//

…

// i have switched the position of a_3 to a_5 for testing clockwise ubwards-counting AND anti-clockwise downwards-counting for any failure!//

//

checking listet words/expressions/values a_n to validity:

- observe the downwards counting in listed int-values!
- try testing in transforming to upwards counting (= standard listing) *]!
- search for a deviated counting punched out of curved/lined seriality!
- search for a slipped letter or invisible sign or a undesirable character!

*] because some CALC-functions need a positive succession/sequence like: 1,2,3,4,…,9,10,11,…, that can failured while counting: 1, 10, 11, 12, …, 19, 2, 20, 21, …//

**math. task:**

f(x) = ??? //function to explane/express a infinite curve/line within 2 dimensions of decimal numbers f(x_n) = a_n(x|y)//

//visualize with every diagram program//

1_LibreOffice-CALC_gelistete Werte abfragen nach identisch UND angenähert höher ODER angenähert niedriger_iN ARBEiT-v0000.ods (38.2 KB)

1_LibreOffice-CALC_gelistete Werte abfragen nach identisch UND angenähert höher ODER angenähert niedriger_iN ARBEiT-v0000.pdf (110.1 KB)

something a little crumb you will/can used.

that’s only a tiny look in µC-programming for just as much understand the CALC-operations/functions/algorithms :: do not despair! and formulate any abstrus question into my belly!

much greetings/hello out of Deutschland (Allemand, Германия, germanskyji, Njemsky, …)