How to code multiple "if" conditions in app designer?

I'm making a calculator app, that uses lots of variables, and one of these variables has a lot of conditions, so i'm trying to make something like

if tsd<=fyd

Sigma_sd=Es*epsilon_s;

elseif tsd>fyd&&Fck<=35&&Delta<=0.17&&fyk=50

Sigma_sd=43.48;

elseif tsd>fyd&Fck>35&&Delta<=0.17&&fyk=50

Sigma_sd=47.5;

elseif tsd>fyd&Fck<=35&&Delta<=0.17&&fyk=60

Sigma_sd=50

elseif tsd>fyd&Fck>35&&Delta<=0.17&&fyk=60

Sigma_sd=51

end

i also want to add more conditions to this code, for when Delta is higher then 0.17, and for delta higher than 0.20, so i think it would be something like this

elseif tsd>fyd&Fck>35&&0.17<delta<=0.2&&fyk=60
    Sigma_sd=51;
    elseif tsd>fyd&Fck>35&&Delta>0.20&&fyk=60
        Sigma_sd=51;

i'm not asking for anyone to make my code, but just to help me to make a coded mult conditions such as my example above.

thanks for any help.

[Augusto]

https://prnt.sc/xwbM7mThsbDC

Answer 1

[Torsten]

if a < b < c

does not work.

You have to split the condition in two:

if a < b & b < c

And

if a = b

does not work.

A logical comparison for equality would be

if a == b

But checking for equality usually does not work because of floating-point arithmetic.

[Augusto]

good to know that! i will use it in my codes for sure.

also, my biggest doubt wasn't answered.

maybe i can ask more clearly: i need to check if one varible is higher than the other, and if it is, i can use it's value to another equation, if not, i have to check on a table for it's value. I know how to check if it is higher or not, but i need to put the table numbers inside my code, and the table has a lots of conditions. Before you think i want a table in my app, that's not it. I need to make the app to check the table for the number, but since the app doesn't work like this, i need to write a code line to fullfill the table requirements.