interp2 -strictly monotomus increasing

Nm=[0.0366242038216561	0.256369426751592	0.671443736730361	1.03768577494692	1.58704883227176	2.00212314225053	2.53927813163482	2.91772823779193	3.40605095541401	3.84554140127389	4.37048832271762	4.84660297239915	5.31050955414013	5.70116772823779	6.07961783439491	6.32377919320595	6.45806794055202	6.51910828025478	6.55573248407643	6.48248407643312	6.40923566878981	6.33598726114650	6.26273885350318	6.21390658174098	6.14065817409767]
tm=[0.485833678632479	2.97491876894587	5.92553696834441	5.95681051392846	8.98528217489712	8.10274242779360	10.4015267390947	9.17522019607471	11.2522554584995	11.4037507008547	13.2569373682494	13.4685308941754	14.0861325375119	13.8739774388098	14.3517545727446	13.1898905990187	12.1320463219057	11.3801661360874	11.1561990863248	9.75845459943019	9.63848959401710	9.51852629230771	9.39856469430197	9.60254185941754	9.19863248363408]
data=xlsread("ss.xlsm");
rrpm=data(2:end,1);
ttorque=data(1,2:end);
epk_eff=data(2:end,2:end);
[ttorque,rrpm]=meshgrid(ttorque,rrpm)
eff_epk=interp2(ttorque,rrpm,epk_eff,tm,Nm);
%%excel sheet attached for eff_data

[KSSV]

Check this:

plot(ttorque,rrpm,'*r')
hold on
plot(tm,Nm,'*k')

The given points (tm, Nm) lies outside the given grid. So the error. Check your data or the logic.

[Harish Vernekar]

the last time you helped me with same kind of answer here only efficiency data is changed other all are kept same.

[Harish Vernekar]

this is previous one

torque = data(2:end,1);

rpm = data(1,2:end);

eff_epk = data(2:end,2:end);

Nm = [2^.5 exp(-1), pi, exp(2)]; % You'll have more sensible parameters here...

tm = [3 30 300 3000];

EPK_operating=interp2(rrpm,ttorque,eff_epk,Nm,tm);

[Asvin Kumar]

It's unclear what you're trying to achieve or what problem you're facing.

Are you seeing any errors? Are you stuck somewhere? What's your question? For the community to help you better, please add descriptions of what you are trying to do.

Have a look at the doc page for interp2 on the 4th and 5th input arguments. You should either change the orientation of Nm or tm. Or you should create a meshgrid out of Nm and tm like you do for ttorque, rrpm.