## use fortran77 in maple...

Hi! I have a lot of programs made by fortran77, can i use this programs under maple10? thanks.

## scientific notation...

Maple 10.(PC Version) In options or somewhere else... Is there a way to set the Scientific Notation threshold. Is there a way to determing what it is? Thanks, Dgiznya

## How to implicitplot/contourplot f(x,y,z) on R2 in ...

Hi, I am very new in maple and I am learning the command plot/contourplot. Given, for example f(x,y,z) = x*y*z defined on x=0..1, y=0..1, z=0..1; I want 1. to implicitplot3d the function f for f(x,y,z)= 1, 1/2, 1/4, 1/8, 1/16, 1/32, ..., 1/2^10 2. to see the previous graphics only when (x>y ∧ y>z) 3. to CONTOURPLOT each "level" of f(x,y,z) obtained in 2 on the plane (x,y),(x,z) and (y,z). Thanks a lot in advance, Jacques.

## Solving nonlinear equations?...

Hi, How to solve 12 nonlinear equations with 6 unknowns with Maple 10 or other software but analytic, not numeric? I was tried with solve(). After waiting 24h computation I was interrupt it. And I don't think that Maple will solve that problem. In begining CPU usage was 100% but latter was 0% and HD always read or write something without stoping.

## How to sum on j1, j2 and boolean expressions?...

I want a function depending on n1 and n2, and a1 and a2, more or less in the following way: sum( sum( ((if ((j1*k1/n1 +j2*k2/n2+k2/n2 > 1/2) &and (j1*k1/n1 +j2*k2/n2 >1/2)) 1 else 0), j1=0..n1), j2=0..n2). How do I write in maple the previous expresion?. That is.. how may I write MYfunction( n1, n2) = sum( sum( BOOLEAN , j1=0..n1),j2=0..n2); where BOOLEAN stands for terms involving j1,j2,n1,n2 and other "constants"? Thanks in advance! Jacques

## F=ma solving...

How does one get Maple to solve F=ma problems like r:=t->; When I try diffeq:=Diff(r,t\$2)+(r.r)^(-3/2)=0; I get > sol:=dsolve(diffeq,r(t)); Error, (in ODEtools/info) expected an ordinary differential equation. Received: 1/(r^2)^(3/2) = 0

## Problem with partial fraction expansion...

I'm posting this on behalf of a user (Peter) who is having problems attaching a file. Peter, I would prefer to try to resolve this issue here then through my e-mail. You will have more "eyes" on the problem on the site. My knowledge of German is limited to menus and street signs. But I am presuming your question is that Maple T.A. is marking the partial fraction expansion answer as incorrect when it is correct. We'll need to see the logic (code) behind the question to deduce where the true source of the problem is. Can you post a regular text post? If not, send me an e-mail. Thanks.

## Where is the problem?...

Hi I work with Maple 9 and I came across to this problem. I don't know where the problem is. >restart: > simplify(convert(sin(1/2*Pi*(-I*x+5)),exp)); > simplify(convert(cosh(1/2*Pi*x),exp)); does it mean that: >sin(1/2*Pi*(-I*x+5))=cosh(1/2*Pi*x); for all x's? Now look at this paradox: >x:=100; > evalf(sin(1/2*Pi*(-I*x+5))); > evalf(cosh(1/2*Pi*x)); where is the problem? cheers Sayed

## 3D Plotting Observation...

I'm working through Francis Wright's book COMPUTING WITH MAPLE. I'm not exactly sure which version of Maple this book is based on. The book's copyright is c2002. If any responders are familiar with this title or author also let me know. I'm looking on some opinions about this person. My question is that Mr Wright in one example stated that 3D plots don't admit multiple plots in [List] format. However when I typed the input: plot3d([sin(x),sin(y)], x = -Pi..Pi, y = -Pi..Pi); I still got a plot instead an error message.

## LaPlace Transforms...

Is there some sort of built in capability for doing LaPlace Transforms? or does one have to do it the "Brute Force" way ? v/r Dan

## a multibody dynamic problem(solving an 2nd order O...

several beams are connected by gemel one after another, the 1st is fixed at one end on the roof, and the last is driven by a force(fx,fy vector summation) at the end point. i am using lagrange method for the virtual displacement of angle theta[i] , and momentum balance in 2 direction (x,and y)to build the model. in the last step, i got an ODE system of 2nd order, but i cant code in maple to solve it. i think it is solveable, (6 equations, 6 unknowns). Kindly let me know how to write the code to solve it! below is the code.

> restart:
interface(warnlevel=0):
with( plots ): with( plottools ):
with( DEtools ): with( PDEtools ):
g:=9.81:
x[0][2]:=0:
y[0][2]:=0:
#initialization function of each beam,in this function, we should give 3 variables, n=the number of this #beam, la=the length of this beam, ma=the  mass of this beam
beams:=proc(n,la,ma)
global l,m,x,y:
l[n]:=la:           #length of  beam n
m[n]:=ma:           #mass of beam n
#initialize the positions of each beam
x[n][2]:=0:        #the x position of the end point of each beam
y[n][2]:=0:        #the x position of the end point of each beam
x[n][1]:=0:        #the y position of the center point of each beam
y[n][1]:=0:        #the y position of the center point of each beam
end proc;
#define the forces that applied on the end of  beam n
Force:=proc(n,fm,fn)
global fx,fy:
fx[n]:=fm:
fy[n]:=fn:
end proc:

## how to solve implicit ODE system like this?...

i have this im plicit ODE system in modeling a multibody dynamic system. theta[1](t), theta[2](t), are the angle displacement of the beams, and they are time depentent, in these 6 equations, i have the term of cos(theta[1](t)), sin(theta[2](t)),cos(theta[2](t)), sin(theta[1](t)), multipling (diff(theta[1](t),t))^2, and diff(theta[1](t),t\$2), which make them implicit equations. there are 6 unknown variables fx1,fx0,fy1,fy0(which are the forces at the end of the beams),and theta[1](t), theta[2](t). i gave the initial condition as ics:={theta[1](0) = 1/6*Pi, theta[2](0) = 1/3*Pi, D(theta[1])(0) = 0, D(theta[2])(0) = 0} Kindly let me know how to write the code to solve it! Thanks. Still below is the code: >