tintegral of a function of the value ...

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Author Message   Geoff Mercer (geoffm) New member Username: geoffm Post Number: 1 Registered: 03-2004 Posted on Thursday, March 11, 2004 - 07:45 pm:    Hi, I have a simple 2d heat diffusion problem in cartesian coordinates. What i want to be able to do is calculate the time integral of a function of the temperature at a given point. for example: find integral 0 to t of exp(temp(1,2)) dt and plot the result versus time is this possible ? Thanks, Geoff Mercer   Robert G. Nelson (rgnelson) Moderator Username: rgnelson Post Number: 123 Registered: 06-2003 Posted on Friday, March 12, 2004 - 07:05 pm:    Use the TIME_INTEGRAL (or TINTEGRAL) function: Definitions tint = tintegral(exp(val(temp(1,2)))) .. plots history(tint)   Geoff Mercer (geoffm) New member Username: geoffm Post Number: 2 Registered: 03-2004 Posted on Tuesday, March 16, 2004 - 06:48 pm:    I tried that previously and keep getting an error 'Illegal Symbol' on the bracket after temp Geoff Mercer   Robert G. Nelson (rgnelson) Moderator Username: rgnelson Post Number: 125 Registered: 06-2003 Posted on Tuesday, March 16, 2004 - 07:27 pm:    Sorry, my typo. The syntax of the VAL command is VAL(<expression>,X_coord,Y_coord) So you need to say tint = tintegral(exp(VAL(temp,1,2))) not tint = tintegral(exp(VAL(temp(1,2))))