## 5 Reputation

11 years, 227 days

## Ok but...

Thank's in maple 11 it work's but I have coords points as [ r, nu, phi] and I want to plot thoses points as in a cartesian coords system as :

X=r*cos(nu)*sin(phi)

Y=r*sin(nu)*sin(phi)

Z=r*cos(phi)

Is there a way without doing thoses projections ?

## Ok but...

Thank's in maple 11 it work's but I have coords points as [ r, nu, phi] and I want to plot thoses points as in a cartesian coords system as :

X=r*cos(nu)*sin(phi)

Y=r*sin(nu)*sin(phi)

Z=r*cos(phi)

Is there a way without doing thoses projections ?

## We will upgrade maple14 next year. Maybe...

We will upgrade maple14 next year. Maybe in february (I hope).

Otherwise I ve maple11 but I never use it because I learn with mapleV ...

This package is valaible on maple11 ? Are there lots of diffenrence beetwen V et 11 ?

## We will upgrade maple14 next year. Maybe...

We will upgrade maple14 next year. Maybe in february (I hope).

Otherwise I ve maple11 but I never use it because I learn with mapleV ...

This package is valaible on maple11 ? Are there lots of diffenrence beetwen V et 11 ?

## maple V...

Hello hirnyk,

I've forgotten to precise that I work with maple V r4 student, and when I ve tried your indication maple answer unknow VectorCalculus package ...

Is this package valable in maple V ?

Thank's

## maple V...

Hello hirnyk,

I've forgotten to precise that I work with maple V r4 student, and when I ve tried your indication maple answer unknow VectorCalculus package ...

Is this package valable in maple V ?

Thank's

## @hirnyk Thank's, arctan(num,den) si ok !...

@hirnyk Thank's, arctan(num,den) si ok !

but I didn't know piecewise function, I will use it !

## @hirnyk Thank's, arctan(num,den) si ok !...

@hirnyk Thank's, arctan(num,den) si ok !

but I didn't know piecewise function, I will use it !

## Thank's...

after looking your file , I understand what I want : a quadrant specific inverse tangent defined by

if denom > 0 nu = arctan(num/denom) + Pi

else nu = arctan(num/denom) + (1-sign(arctan(num/denom))*Pi

or by :

if denom > 0 num > 0  nu = arctan(num/denom)

if denom > 0 num < 0  nu = arctan(num/denom) + 2*Pi

if denom < 0 num > 0  nu = arctan(num/denom) + Pi

if denom < 0 num < 0  nu = arctan(num/denom) + Pi

Is there a way to do that in maple V student ?

Thank's

EDIT : I try arctan(num,denom) and it seems to work ...

## Ok, I ve a look of what you said hirnyk,...

Ok, I ve a look of what you said hirnyk, so there is no problem in maple ...

the function can be written as nu = arctan ( num/ den)+ alpha*Pi ,and I ve to specify if den < 0 alpha = 1 and if den>0 alpha=0 to have that I want to modelise.

I will try to write this in maple but if somebody can help me it will better because I am not sure to achieve by myself.

I tried with a procedure but no way ...

I wrote :

P1:=proc(n1,n2)
local alpha;
global nu;
if n1>0 then
alpha:=0
else
alpha:=1
fi;
nu:=arctan(n2/n1)+alpha*Pi;
end;

but when I write P1(ntest,ntest2); maple say error in P1 cannot evaluate boulean.

Can somebody help me please ?

## Ok, I ve a look of what you said hirnyk,...

Ok, I ve a look of what you said hirnyk, so there is no problem in maple ...

the function can be written as nu = arctan ( num/ den)+ alpha*Pi ,and I ve to specify if den < 0 alpha = 1 and if den>0 alpha=0 to have that I want to modelise.

I will try to write this in maple but if somebody can help me it will better because I am not sure to achieve by myself.

I tried with a procedure but no way ...

I wrote :

P1:=proc(n1,n2)
local alpha;
global nu;
if n1>0 then
alpha:=0
else
alpha:=1
fi;
nu:=arctan(n2/n1)+alpha*Pi;
end;

but when I write P1(ntest,ntest2); maple say error in P1 cannot evaluate boulean.

Can somebody help me please ?

## Hello and sorry to be late,   &nbs...

Hello and sorry to be late,

nu := arctan(((L*cos(theta2)-L*cos(theta1))*(-3/2*R-1/2*L*sin(theta3)-L*sin(theta1))-(-3/2*R-1/2*L*sin(theta2)-L*sin(theta1))*(L*cos(theta3)-L*cos(theta1)))/(1/2*3^(1/2)*(R+L*sin(theta2))*(L*cos(theta3)-L*cos(theta1))+1/2*(L*cos(theta2)-L*cos(theta1))*3^(1/2)*(R+L*sin(theta3))))

This equation modelize a robot's orientation, I ve a  mock up of this robot so R and L are value and no time dependant. I have substitue theta3 by value to modelize a problem in motor 3.

So I can say in reality there is no discontinuity in the orientation (nu = azimut).

## Hello   the condition define thet...

Hello

the condition define theta3 as a function of theta1 and theta2 but I think maple won't be abble to compute fsolve and find theta3 = .....

That's why I wonder if maple can plot with a condition without substitute theta3.

But I will try your example this day.

Thank's

## Hello   the condition define thet...

Hello

the condition define theta3 as a function of theta1 and theta2 but I think maple won't be abble to compute fsolve and find theta3 = .....

That's why I wonder if maple can plot with a condition without substitute theta3.

But I will try your example this day.

Thank's

## Hello and sorry to be late,   as ...

Hello and sorry to be late,

as far as I understand, you have plotted the function defined by : cos(theta1)*tan( tetha2)+ acos(theta3) = L

This function was just an example bu not the true, nevermind.

I try to explain better my problem : I ve 3 functions defined by 3 parameters, thoses 3 functions represent a vector :

X = f(theta1,theta2,theta3)

Y = g(theta1,theta2,theta3)

Z = h(theta1,theta2,theta3)

If I want to have a surface and not a solid region trace out by the vector [X,Y,Z] when theta1,2,3 vary from 0 to 90, I have to add condition which link theta1,2,3 for exemple sqrt ( X^2 + Y^2 + Z^2) = Radius

This condition will link theta1,2,3 and I would like to plot only the surface = equation vector + condition, is there a way to plot a function with condition on parameters ?

for example :

assume (sqrt ( X^2 + Y^2 + Z^2) = Radius);

plot3d({X,Y,Z}, theta1=0..Pi, theta2=0..Pi, ---------etc--------------);

in this plot I didn't tell maple range for theta3 because theta3 is defined by the condition sqrt ( X^2 + Y^2 + Z^2) = Radius when theta1,2 are defined.

I hope I am more precise.

Thank's

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