The numbers below are in a file on my machine called mpltest.dat located in C:\temp on my Windows PC. 1 1 2 4 3 9 4 16 5 25 6 36 7 49 8 64 9 81 10 100 These are the commands to read in this file and assign it to the variable Data. From there you can do what you just described. > restart: > Data:=readdata("c:/temp/mpltest.dat",integer,2); > Data[3,2]; 9 The last command returns the number 9, as it should. ?LinearAlgebra,Details will display the help page that will allow you to access the commands you are looking for to extract columns or rows. Regards, Georgios Kokovidis Dräger Medical

Using the code above as an example, modifiy the last line as below and add the second line in order to write the output to a file. In my particular case, I am writing the file to the temp directory on my "C:\" drive. The name of the file is data.dat. Then you can read it into whatever program you want by opening the file. > sol:=[seq( evalf(eval(x(t),t=i)) ,i=1..10)]; > writedata("c:/temp/data.dat",sol); Regards, Georgios Kokovidis

Using the code above as an example, modifiy the last line as below and add the second line in order to write the output to a file. In my particular case, I am writing the file to the temp directory on my "C:\" drive. The name of the file is data.dat. Then you can read it into whatever program you want by opening the file. > sol:=[seq( evalf(eval(x(t),t=i)) ,i=1..10)]; > writedata("c:/temp/data.dat",sol); Regards, Georgios Kokovidis

See ?textplot > restart: > with(plots): > p1:=plot(x^2+5,x=-3..3): > p2:=textplot([0.3,5.2,"Vertex"],color=blue): > display(p1,p2); Regards, Georgios Kokovidis

?int will open up the help page. Scroll all the way to the bottom of the help page and click on int/details. This will display the help page that you are looking for. You can also get there by typing ?int/details right at the Maple prompt. Regards, Georgios Kokovidis

?int will open up the help page. Scroll all the way to the bottom of the help page and click on int/details. This will display the help page that you are looking for. You can also get there by typing ?int/details right at the Maple prompt. Regards, Georgios Kokovidis

Introduction to Maple by Andre Heck Maple By Example, Third Ed by Martha L. Abell, James P. Braselton These will get you going in the right direction. You can also download a whole bunch of pdf files that will guide with specific maple solution to problems. As an example, I would do a google search as follows, for maple help with the Quadratic Formula: maple Quadratic Formula filetype:pdf Good luck. Regards, Georgios Kokovidis

Greetings again. The grad function from the book that you mentioned is missing. The authors have neglected to include it, therefore all of the programs that call it will fail. Matlab does have a "gradient" function built in, but changing the call from grad to gradient will not get you there. I tried it and the errors are worse. I do not have any advice for you other than trying to write your own "grad.m" function, or contacting the authors and asking them for it. Regards, Georgios Kokovidis P.S. You can also post your question on the Matlab usenet group and see what happens. Good luck.

Greetings again. The grad function from the book that you mentioned is missing. The authors have neglected to include it, therefore all of the programs that call it will fail. Matlab does have a "gradient" function built in, but changing the call from grad to gradient will not get you there. I tried it and the errors are worse. I do not have any advice for you other than trying to write your own "grad.m" function, or contacting the authors and asking them for it. Regards, Georgios Kokovidis P.S. You can also post your question on the Matlab usenet group and see what happens. Good luck.

Below is a parabolic function defined for illustrative purposes only. The range of the plot is from 0 to 5. The range of the bounded area is within this range and filled to show that it is within the initial limits. > restart: > with(plots): > a1:=plot(-(x^2)+25,x=1..4,filled=true,color=blue): > a2:=plot(-(x^2)+25,x=0..5,thickness=3, color=red): > display(a1,a2); If this is not what you are looking for, then I do not fully understanding your question. Regards, Georgios Kokovidis

Greetings. I again ran your example. Part 1 is the way you have it. Part 2 is the same except for the last line. Your original example used the subs command. Here you are not using it. I modified the last line of your code in part 2 below. My results were the same as in part 1. I might be missing something. Let me know. Part(1) > restart: > posConst:= AndProp( realcons, RealRange(Open(0),infinity) ): > assume(m::posConst ); > assume(g::posConst ); > assume(A::realcons ); > assume(sigma::realcons ); > a:=m*diff(y(t),t,t)=m*g-sigma*A*diff(y(t),t); > y(0)=h,D(y)(0)=0; > b:=dsolve(a); > eval(rhs((b)),{A=2,m=50,sigma=1.2}); Part(2) > restart: > posConst := AndProp( realcons, RealRange(Open(0),infinity) ): > assume( m::posConst ); > assume( g::posConst ); > assume( A::realcons ); > assume( sigma::realcons ); > a:=m*diff(y(t),t,t)=m*g-sigma*A*diff(y(t),t); > y(0)=h,D(y)(0)=0; > b:=dsolve(a); > subs({A=2,m=50,sigma=1.2},rhs((b))); Regards, Georgios Kokovidis

Greetings. I again ran your example. Part 1 is the way you have it. Part 2 is the same except for the last line. Your original example used the subs command. Here you are not using it. I modified the last line of your code in part 2 below. My results were the same as in part 1. I might be missing something. Let me know. Part(1) > restart: > posConst:= AndProp( realcons, RealRange(Open(0),infinity) ): > assume(m::posConst ); > assume(g::posConst ); > assume(A::realcons ); > assume(sigma::realcons ); > a:=m*diff(y(t),t,t)=m*g-sigma*A*diff(y(t),t); > y(0)=h,D(y)(0)=0; > b:=dsolve(a); > eval(rhs((b)),{A=2,m=50,sigma=1.2}); Part(2) > restart: > posConst := AndProp( realcons, RealRange(Open(0),infinity) ): > assume( m::posConst ); > assume( g::posConst ); > assume( A::realcons ); > assume( sigma::realcons ); > a:=m*diff(y(t),t,t)=m*g-sigma*A*diff(y(t),t); > y(0)=h,D(y)(0)=0; > b:=dsolve(a); > subs({A=2,m=50,sigma=1.2},rhs((b))); Regards, Georgios Kokovidis

I made an error in my initial reply. I solved for the first zero crossing. The reply by Joe Riel is the correct one for finding the "minimum". Sorry for any confusion. Regards, Georgios

I made an error in my initial reply. I solved for the first zero crossing. The reply by Joe Riel is the correct one for finding the "minimum". Sorry for any confusion. Regards, Georgios

Those are not coordinates. From ?roots: The roots are returned as a list of pairs of the form [[r1, m1], ..., [rn, mn]] where ri is a root of the polynomial a with multiplicity mi. The 1's are the mi's in your case. After giving it some thought, I think for your given problem it would be best to use; > with(Student[Calculus1]): > Roots(L); This return [-3, -1, 1], which is exactly what you are looking for. Those points correlate to your graph of the function as the zero crossing points. Sorry for the confusions with "roots" function. Regards, Georgios Kokovidis