as a structural engineer, i deal with relatively simple mathematics, but with a high number of variables and assumptions during the design process.

i am looking for a handheld calculator which i can program with the different equations i use many times each day.
each equation has many variables, and many conditions. the best method of work for me is to use excel spreadsheets which i have built over the years(i use the "if" function and the "vlookup" function all the time)
i am not farmiliar with graphing calculators but am looking for a device into which i can program all these equations so i can take it with me to meetings and site visits so that i can evaluate on the spot

which graphing calculator will best suit my needs, and what programming language does it use

are there any handheld calculators which can be programmed in excel? or in MATLAB?

Could you list one such equation so that we could see what kind of equations you work with? And thus have a better idea what to recommend you?

for example, for the following given input variables
b, h, ds, Md, fcd

the end result i need is "As"

and the way to calculate "As" is

1. d=h-ds
2. w=max(0.1, (1-sqrt(1-2*Md/(b*d^2*fcd))))
3. z=d*(1-w)
4. As=Md/(3.5*z)
5. if(As<0.0015*b*d) --display--> As<As,minimum=0.0015*b*d


this is just one simple example, there are others many "if" conditions, but i think this is one that is relatively straightforward as an example


aas an example of a longer step - see the attached equation copied from one cell of one of the spreadsheets i work with

=IF(AND(O10=1,L12="רגיל"),"L+2*D*ψ=",IF(AND(O10=2,L12="רגיל"),"1.0*L=",IF(AND(O10=3,L12="רגיל"),"0.85*L=",IF(AND(O10=4,L12="רגיל"),"0.7*L=",IF(AND(O10=1,L12="מקטין יציבות"),"1.2*(L+2*D*ψ)=",IF(AND(O10=2,L12="מקטין יציבות"),"1.2*L=",IF(AND(O10=3,L12="מקטין יציבות"),"1.0*L=",IF(AND(O10=4,L12="מקטין יציבות"),"0.85*L=",0))))))))

THIS I DOT EXPECT YOU TO TRY FIGURE OUT

Well, TI-BASIC on the 84+ line of calculators are pretty easy to get to work with regard equations and such.

To answer your question regarding spreadsheets. Both the Nspire CX and the HP Prime have spreadsheet apps; however I am unsure of how usable they are in comparison to say Excel.

Please forgive my ignorance, but is " רגיל " part of a language? If so, then that makes it a variable, yes? IF not, what is it?

It looks like Hebrew, and that's a string, so presumably Excel has reasonable international character support (as you'd expect).

As tifreak8x says, TI-BASIC on the TI-84 Plus series is more than capable of performing those kinds of computations, once you learn how to program in it. May I (biasedly) recommend "Programming the TI-83 Plus/TI-84 Plus" as an easy place to start?

That Excel formula doesn't look intimidating at all; in fact's it's mostly IF(AND())s nested within each other. It could be entirely replaced by writing a script in BASIC.

https://www.amazon.co.uk/Casio-engineering-specialized-fx-FD10-Pro/dp/B00JVHNESS
I don't know much about this model but it seems specifically designed for engineers, has rugged design and programmable by PC
I wouldn't be surprised if it supports spreadsheets as well but not sure how advanced