Advanced Search

MaplePrimes Questions

isolve and _SolutionsMayBeLost...

Asked by: vv 13837
isolve
November 08 2018
2  7
> 

sys:={x+y=10,x^2-y^2+z^2=1};

{x+y = 10, x^2-y^2+z^2 = 1}

 (1)
> 

isolve(sys, n);

{x = -(1/20)*(1+20*n)^2+101/20, y = (1/20)*(1+20*n)^2+99/20, z = 1+20*n}

 (2)
> 

_SolutionsMayBeLost;  # It was set in Maple 10 or so!  E.g. x=5,y=5,z=-1 is not found.

_SolutionsMayBeLost

 (3)
> 

# Workaround
> 

yz:=eliminate(sys,x);

[{x = -y+10}, {z^2-20*y+99}]

 (4)
> 

S:=isolve(yz[2], n);

{y = 20*n^2-38*n+23, z = 19-20*n}, {y = 20*n^2-22*n+11, z = 11-20*n}, {y = 20*n^2-18*n+9, z = 9-20*n}, {y = 20*n^2-2*n+5, z = 1-20*n}

 (5)
> 

map(u -> ( u union eval(yz[1],u) ), [S])[];  # The correct solution

{x = -20*n^2+38*n-13, y = 20*n^2-38*n+23, z = 19-20*n}, {x = -20*n^2+22*n-1, y = 20*n^2-22*n+11, z = 11-20*n}, {x = -20*n^2+18*n+1, y = 20*n^2-18*n+9, z = 9-20*n}, {x = -20*n^2+2*n+5, y = 20*n^2-2*n+5, z = 1-20*n}

 (6)
> 

 

Differential forward quote...

Asked by: brian bovril 914
input 1dmath
November 07 2018
0  2

This may seem a bit trivial, but I prefer f'(x) to writing diff(f(x),x) in 1D input. How to achieve?

differential.mw


 

15

  

"maple init loaded..."

 (1)

In Document mode, this works fine.

f := proc (x) options operator, arrow; x^2 end proc

proc (x) options operator, arrow; x^2 end proc

 (2)

diff(f(x), x)

2*x

 (3)

But I mainly use Worksheet (1D) mode, and I can't seem to acheve the same, without using diff(f(x),x)

``

f:x->x^2

proc (x) options operator, arrow; x^2 end proc

 (4)

f'(x)

Error, unexpected single forward quote

  

``


 

Download differential.mw

 

Pulling power into exponential under assumptions...

Asked by: digerdiga 390
exponential simplification combine
November 07 2018
1  9

Hello,

Simple question:

Why does

restart;

(exp(I*t))^q;

`assuming`([simplify(%)], [t > 0, t < 2*Pi, q > 0, q < 1])

 

 

not simplify to exp(I*t*q)

?

Physics package archive?...

Asked by: Christopher2222 6030
package physics
November 07 2018
1  6

The Maplecloud and maplesoft web pages only have the latest version of the physics package. 

Is there an archive of older physics packages?  ie. the latest versions to go with each of the older versions of Maple?

how to get maple to automatically simplify...

Asked by: itsme 774
simplification trig
November 07 2018
0  6

does anyone khow to force maple to automatically simplify expressions that look like this:

restart:

cc:=arctan(sin(phi)/cos(phi))-arccos(cos(phi))      
simplify(cc) assuming phi::real; #should be zero

i've played with convert/expand/simplify and in certain cases of course i can force maple to do this... (kind of manually).. but was hoping this could be more automatic.

thanks!

 

Round with units...

Asked by: bliengme 70
round units
November 07 2018
1  3

The round(x) statement rounds x to the nearest integer but if x has unirs it appears not to work. Known bug?

RoundUnits.mw
 

> 

restart
> 

a := 15; b := 5.3
> 

c := (1/100)*a+b

5.450000000

 (1)
> 

c := round(c)

5

 (2)
> 

``
> 

A := 15*Unit('cm'); B := 5.3*Unit('m')
> 

C := A+B

15*Units:-Unit(cm)+5.3*Units:-Unit(m)

 (3)
> 

C := simplify(C)

5.450000000*Units:-Unit(m)

 (4)
> 

Cr := round(C)

round(5.450000000*Units:-Unit(m))

 (5)
> 

``


 

Download RoundUnits.mw

 

Gamma function problem...

Asked by: miroslav 15
gamma
November 07 2018
1  3

Hello, I am getting the following output from maple: (-ln(lambda)-gamma-ln(k+b))/(k+b) . I have all variables (lambda, k, b) but not gamma and I am not sure what actually it is. I believe it is some kind of Gamma function but I cannot find any expressions for that. Ussually for gamma function I get something like GAMMA(x). Does someone know what this lower case gamma is?

How do I write a simple procedure to evaluate the ...

Asked by: Teep 200
November 07 2018
0  4

I wish to write a simple procedure to evaluate the Poisson quantile function, F, for many possible parameter values, lambda.

The Maple commands to evaluate F for individual lambda values works just fine, however, I have tried to write a simple procedure to evaluate F for prescribed lambda values (imported from Excel) but to no avail. I'm missing something quite basic, I'm sure.

Can anybody offer a suggestion please? Thanks.

 

Inverse_Poisson_Procedure.mw

how i can Substituting......

Asked by: torabi 90
substitution
November 06 2018
0  4

i want to gain diff(p(t), t) and diff(q(t), t) and Jacobian matrix
 according to the attached pdf file.

please help me.

thanks

simplify.mw
 

> 

k := diff(a(t), t) = -mu*a(t)-(1/4)*alpha6*a(t)*sin(gamma(t))

diff(a(t), t) = -mu*a(t)-(1/4)*alpha6*a(t)*sin(gamma(t))

 (1)
> 

j := a(t)*(diff(gamma(t), t)) = 2*a(t)*sigma-(6*(1/8))*(alpha1-alpha2+(1/3)*alpha3)*a(t)^3-(1/2)*alpha6*a(t)*cos(gamma(t))

a(t)*(diff(gamma(t), t)) = 2*a(t)*sigma-(3/4)*(alpha1-alpha2+(1/3)*alpha3)*a(t)^3-(1/2)*alpha6*a(t)*cos(gamma(t))

 (2)
> 

"p(t):=a(t)*cos(gamma(t))"

proc (t) options operator, arrow, function_assign; a(t)*cos(gamma(t)) end proc

 (3)
> 

"q(t):=a(t)*sin(gamma(t))"

proc (t) options operator, arrow, function_assign; a(t)*sin(gamma(t)) end proc

 (4)
> 

diff(p(t), t)

(diff(a(t), t))*cos(gamma(t))-a(t)*(diff(gamma(t), t))*sin(gamma(t))

 (5)
> 

(-mu*a(t)-(1/4)*alpha6*a(t)*sin(gamma(t)))*cos(gamma(t))-a(t)*(2*sigma-(6*(1/8))*(alpha1-alpha2+(1/3)*alpha3)*a(t)^2-(1/2)*alpha6*cos(gamma(t)))*sin(gamma(t))

(-mu*a(t)-(1/4)*alpha6*a(t)*sin(gamma(t)))*cos(gamma(t))-a(t)*(2*sigma-(3/4)*(alpha1-alpha2+(1/3)*alpha3)*a(t)^2-(1/2)*alpha6*cos(gamma(t)))*sin(gamma(t))

 (6)
> 

diff(p(t), t)

2*t

 (7)
> 

``


subs.pdf

Download simplify.mw

 

 

Trouble with a simple procedure...

Asked by: PhilipKroon 10
proc
November 06 2018
1  4

Hi

I am having some trouble with a procedure. One of the procedures arguments is a mathematical function g(var). For simplification lets say I wish to make a procedure which calculates some values of the unknown function, g: 

SomeProc:=proc(g,var:=x)
f(var):=g
return f(2)
end proc

This does not seem to work. No matter what value of var is inserted into f, the return is g(var). 

Any help would be much appreciated:

Combining log10...

Asked by: dareimert 35
November 06 2018
0  2

How do I combine log10 terms. I can do it with natural logs but I have not been able do do it with log10.

 

    

How do I replace an expression to make the equati...

Asked by: José Goulart 25
November 06 2018
1  5

 

Hello, I would like to make my polynomial equation simpler by replacing every coefficient of each degree in s by any constant.

For example, one of the variable solutions it is:


How can i re-write this equation in the form, lets say, C0+C1*s+C2*s^2+C3*s^3?

Data from a graph...

Asked by: shahid 15
getdata plot3d plotting
November 06 2018
0  4

I draw a 3d graph and now i want the table of this graph. how can we get a table from the data of a plotted graph.

May grapg was obtained from the following commands

 

restart;
plot3d(1/2*(q^(2*n)-5.*q^n+(2.*q-1)^n+3), q = 2 .. 15, n = 2 .. 20);
 

how to get number from variable[type-symbol]?...

Asked by: Rohith 65
string name
November 06 2018
0  6

How can one the last value of variable

when I have variables Like C1;C2,C3....., F1,F2,F32,....so on

always number would be at last of the variable.

Depending upon the number in the variable I need to call values from other list. It would be really helpful to know how one can get the number present in variable?

Runge-Kutta 4th order...

Asked by: Goddi 15
ode homework
November 06 2018
3  4

Hi, I am working on an assignment and have some doubts about my solution to plotting the position of an anharmonic oscilliator with the Runge-Kutta method.

My attempt on the problem:

Handin_2.mw

A picture of the problem is attached below. In addition to this, we are to repeat the problem with k = 0.1 (f = 0 still), and k = 0.1 and f = 0.5. 

 

First 754 755 756 757 758 759 760 Last Page 756 of 2426