Items tagged with function

Hello,

I have this list :
T:=[alpha(t),beta(t)]

I would like to create this list automatically:

Tmod:=[alpha_,beta_]

In other words, how can I remove the 3 characters "(t)" and replace it by "_"

Do you have ideas to do so ?

Thanks a lot for your help

Suppose I have a function like this: f=cos(2t/m)+cos(2(t+5)/m).

 

Now for each fixed m, we get the maximum value of f. Then I want to build a plot where x-axis is m and y-axis is f, how could I do that? Please help!

 

I am wondering why Maple does this.

> f:=x^2
> f(3)
output: x(3)^2

I understand the difference between an expression and a function. If f is an expression, shouldn't it ouput  x^2(3). Why is the output x(3)^2?

When I enter f*3 or f*(3) then I get the correct expression.

Here is a screenshot. http://prntscr.com/a7u9hm

Here is image inserted with a slightly different function

 

Also while I am here, what exactly does g(x):= x^2 do? when i enter g(3) I get g(3) back.

g(x) is neither a function nor an expression.

screenshot http://prntscr.com/a7ua75



Consider, say, the following third order derivative:

expr := diff(f(x,y),x,y$2);

Does there in Maple exist some built-in functions for extracting from such an expression 1.) the function being differentiated, and 2.) the coordinates being differentiated with respect to? Using op(expr) is of no immediate avail as it returns only a second order derivative (as the first operand), and one of the coordinates being differentiated with respect to (as the second operand).

It is, of course, possible to make ones own function for extracting these two quantities, a crude example being

splitDeriv := proc(expr,coords::expects(list) := [])
   if PDETools:-difforder(expr) > 0 then
      splitDeriv(op(1,expr),[coords[],op(2,expr)])
   else
      expr,coords
   end if
end proc:

for which

splitDeriv(expr);

But it would be much nicer to use built-in functions. And perhaps such functions do exist. If so, I am unable to locate them. Perhaps I am just being stupid, for the problem seems rather elementary.

Hello,

I am trying to plot 3d scattered data as a 2d scatterplot with the third dimension being displayed as colour or a line that separates the value of the two functions (for example, the higher value and lower value at that point). I attached the file. I have two functions and several parameters that are constant. Here, I want to use P[A] on the x-axis, and P[B] on the y-axis. The z dimension is the profit functions, either Profit[1] or Profit [2]. I want to show them in colors like the highest one is red and the lower one is green, or something similar.  P[A] and P[B] are probability values and P[B] is between 0 to 0.50 with 0.01 increments, while P[A] is always less than P[B]. The file is here: example_file.mw

Example;

P[A] := 0 ..P[B]-0.01

P[B] := 0 ..0.50

Anyone please help me to code this problem.Thanks,

YC

map(f, foldl(`*`, 1, a, b));
foldl(`*`, 1, map(f,a), map(f,b));

map(f, foldl(`+`, 0, a, b));
foldl(`+`, 0, map(f,a), map(f,b));

i discover it can auto calculate ring homomorphism, 

if i define a function f below

factor(map(f, foldl(`*`, 1, a, b))+map(f, foldl(`*`, 1, b, c))) = map(f, foldl(`*`, 1, a, c));

how to convert this f into a function with two input parameters?

 

Hello,

I have just discovered the existence of element-wise operators which uses the symbol tilde

In the help, I saw this exemple

sin~(<1,2,3>);
Vector[column](%id = 18446744073926346622)

which is identic to a result that I can find with map function :

map(sin,<1,2,3>);
Vector[column](%id = 18446744073926346982)

What can Element-wise operators bring more than the map function ?

Do you often use this symbol ?

Thanks a lot for your information.

Hi there, 

I'm trying to find a way to find the Preimage for a single point (or a small set) of a complex rational function. I've tried with the command RationalMapPreimage, which sounds like the thing to try, but I can't get my head around how this command works?

(For context, I'm trying to find the preimages of a the fixed/critical/postcritial points of a function something like f(z)=(z2-1)/(z2+1))

Many Thanks

Dear all;

 

Hello everybody, I need your help to dispaly some values obtained using my function f. When I run the code there is no results obtained. Many thanks.

restart:

# The vectors e(i) satify the folowing conditions
e(0)*e(1)=e(n-1) assuming  1<n;
e(0)*e(0)=e(2):
e(1)*e(1)=e(n-1) assuming  1<n: :
e(2)*e(1)=e(n) assuming  1<n:
#
for i from 1  to n-1 do
e(i)*e(0)=e(i+1);
end do:

# We define the function f
f:=e(0)->e(0)+(n-3)*e(1);
f:=e(1)->(n-2)*e(1);
for i from 2  to 3 do
f:=e(i)->(n+i-3)*e(i)+(i-1)*(n-3)*e(n-3+i);
end do:

for i from 4 to n do
f:=e(i)->(n+i-3)*e(i)
end do:

# We define the two vectors
x:=sum(alpha(k)*e(k),k=0..n);
y:=sum(beta(k)*e(k),k=0..n);

#Question : I would like to compute the following  but there is no display of the solution. 
(x*y);
f(x*y);
f(x);
f(y);
x*f(y);
f(x)*y;
f(x*y)- f(x)*y-x*f(y);

Hello,

I have a vector with 4 components. Each component is a polynom.

N := Vector[row](4, {(1) = -(1/2)*t^3+t^2-(1/2)*t, (2) = (3/2)*t^3-(5/2)*t^2+1, (3) = -(3/2)*t^3+2*t^2+(1/2)*t, (4) = (1/2)*t^3-(1/2)*t^2});
N[1]+N[2]+N[3]+N[4];
sum(N[i], i = 1..4);

I don't why the function sum doesn't work in this case. If i do the sum like this N[1]+N[2]+N[3]+N[4];, it works but it doesn't work with the use of the sum function.

Thank you for your help.

 a new function from an existing function and how?

I try to assign a value "y" function "g" but not working. Should be g(0.5,y)=800, but it is not appear in screen. Regards.

value_function.mw

``

restart

``

``

``

g(.5, y) := 200*y;

200*y

(1)

y := 4;

4

(2)

g(.5, y)

g(.5, 4)

(3)

``

``



Download value_function.mw

 

hi. i am tottaly new to the maple and i have a problem.

consider function f with variables x & y which are not independent. x & y are functions of t and the relation is unknown.

for example i wanna to the below job:

define f as f=x^2+y^2

differentiate it with respect to t : diff(f,t) which should give me 2(dx/dt)x+2(dy/dt)y

i've googled it alot and i couldn't find anything usefull.

(the problem is how to set x as a function of t with unknown relation and use it in another function and then differentiate it with respect to t)

thanks alot :)

 

Hello,

I've tried to find the solution to my problem, but none of my attempts was succesful.

I have a function which is one-to-one in a particular domain which I am interested in. I would like to get the inverse function of it only in this domain. Here is my function and plot for xp=0..10000:

x := xp-> (-1)*720.5668720*sinh(0.2043018094e-3*xp-0.8532729286)+84952.59423+4.014460003*10^5*arcsinh(0.1219272144e-1*sinh(0.2043018094e-3*xp-0.8532729286)-0.2032498888)

I would appreciate any help,

Iza

Hello

I want to plot in semilog graph the attached function.where b from 1 to 5 and R from 1 to 100000(in logR)I tried with the plot builder but i think i am doing smthing wrong

``

 

R = 2*b*(b^2-9*b-6)/(10*b^3+21*b^2+16*b+4)

(1)

;

 

 

 

;

;

 

 

Download re.mw

1 2 3 4 5 6 7 Last Page 2 of 27