Undefined function or variable 'Tw'

Okay I am trying to build a function and execute it and I keep getting an error. Any help would be appreciated.

function[Td,RH]=Dewpoint(T,Tw,Psta)

Es=6.112^((17.67*T)/(T+243.5)); Ew=6.112^((17.67*Tw)/(Tw+243.5));

E=Ew-(Psta*(T-Tw))*0.00066*(1+0.00115*Tw); RH=100*(E/(Es)); Td=(243.5*log(E/6.112))/(17.67-log(E/6.112)); end

 That's my function. When I try to execute it in a new script file I get this error.

>> [Td,RH]=Dewpoint(25,19,985); fprintf('For a wet bulb temperature of %.2f, dry point temperture of %.2f and pressure of %.2f, the dew point temperature and relative humidity are %.2f and %.2f.\n',Tw,T,Psta,Td,RH) Undefined function or variable 'Tw'.

Help is greatly appreciated as I am new to using Matlab.

Answer 1

[Honglei Chen]

Looks like the issue is more on the fprintf line, not the function call. Indeed you are using variable name Tw in fprintf without defining it.

HTH