MaplePrimes Questions

Given some expression, I want to replace each exp(.....) in it with something else.

This is what I currently do. First I find all the exp() terms, then using a loop and use subs  like this


#find all exp terms

Now, lets says I want to replace each with Z

I tried to use but that did not work.

So now I am doing this

for item in s do

is it possible do this without a loop? could not do it using ~

With map, I can do this map(x->subs(x=Z,expr),s) but this does not replace it inside expr where I want. 

Assignment is not allowed inside the above so I can not do  this map(x->expr:=subs(x=Z,expr),s)

And if I do expr:=map(x->subs(x=Z,expr),s)  it does not work either. it gives


How to do the replacement without using a do loop? 



I have the following question, plot the graph of mu=5*log_10(D_L/10) where D_L=(c/H_0)*\int_0^z dz'/[A(1+z')^4+B(1+z)^3+C]^{1/2} with resepct to z, where A,B,C are numerical values given beforehand, and c is the speed of light and H_0 is the current Hubble constant.


Can someone please help with this simple plotting assignment.


Thanks, just by experience, can I learnt these syntax languages.


Peace out!


Might anyone be able to tell me what I am doing wrong trying to solve for this ODE?

Thanks so much!

Hi there,

Can someone explain to me why is it happening? If smaller equal than coloured well, if smaller then just the equal line appears. Why?

dm1 := .23; pm12 := .7; dm12 := .23;
inequal(pm1*(dm12+am21)-pm12*(dm1+am21) <= 0, pm1 = 0 .. 1, am21 = 0 .. 1, color = "Nautical 1");


inequal(pm1*(dm12+am21)-pm12*(dm1+am21) < 0, pm1 = 0 .. 1, am21 = 0 .. 1, color = "Nautical 1")

Thank you!

PDEtools[declare](f(x), prime = x);
N := 4;
f(x) :=  sum(p^i*f[i](x), i = 0..N):
HPMEq := (1 - p)*diff(f(x), x $ 3) + p*(diff(f(x), x $ 3) + 1/2*diff(f(x), x, x)*f(x));
for i from 0 to N do
    equ[1][i] := coeff(HPMEq, p, i) = 0;
end do;
cond[1][0] := f[0](0) = 0, D(f[0])(0) = 0, D(f[0])(5) = 1

for j to N do
    cond[1][j] := f[j](0) = 0, D(f[j])(0) = 0, D(f[j])(5) = 0;
end do

for i from 0 to N do
    dsolve({cond[1][i], equ[1][i]}, f[i](x));
    f[i](x) := rhs(%);
end do;
f(x) := evalf(simplify(sum(f[n](x), n = 0 .. N)))

convert(f(x), 'rational')

subs(x = 2.4, diff(f(x), x))

How to sort a matrix based on one particular column in that matrix


Matrix ([[21,30],[8,4]]).  Has to sorted on column one only and output. Matrix ([[8,4],[21,30]]). In this I have given only 2×2  it could be a n×n

Without too much code



Is it  possible to draw an ellipse inscribled in a given triangle and we know its orthoptist circle ? Thank you very much.

## I hope this works. I can't seem to paste my MW file in this window in a readable format.


This is the Maple code


simplify(result,size) ;

Any suggestions?



How to find a rational function with give horizontal asymptotes: y=0.7, y=-0.7 and vertical asymptotes: x=0.001, x=-0.001?


I have a list with a large number of elements and I need to partition it in chunks of a specific size.  Here is my attempt

listpart := proc(cond::list,nchunk::nonnegint:=1000)
if numelems(cond) < nchunk then
end if:
end proc:

It does not run as fast as I thought.  I am not even sure if Threads:-Seq could be used in this case.  Please tell me what I am doing wrong and how I can modify the code to get a faster response.  

Many thanks



Hello all

could anyone tell how to solve following nonliner equations numerically.

f '''' - c1(g'') + R(f ' f '' - f f ''' )=0

g'' + c2(f '' -2g) -c3(f g' - f ' g)=0

f ' (-1)=0,   f ' (1)=0,   f(-1)=1-A, F(1) =1, g(-1)=0, g(1)=0

c1=3.2, c2=3.3, c3=3.4, R= -10 and A=1.6 are constants.   

please help to find solution  numerically and how to plot. 

Thanks in advence



I am trying to calculate an integral involving dirac delta as given below


However, Maple returns the integral unevaluated as


How can I get it evaluated? the result should be 3 here.

Thanks in advance.

         Hello each and everyone,

I have a problem with updating the Physics Package. (At the moment I run version 709)

But when I try to update to version 710 I have the following error (see the screenshot)

I don't know what's happening.

Kind regards to all.


I try to make a procedure for this 

Was it by a example of Riemann sum that  x-values in a array are stored for  numerical value, but in this task it seems that the array must be filled with the symbol x1,x2 , etc 

Should this be needed ?




excset  3  task4


Was it first for a partition about a interval ( example Riemannn sum) that i got  a list of numeric values

 a:= 0: b:= 5: N:= 30: i= 0..N :

X:= Array(0..N, [seq(j, j=a..b, (b-a)/N)]);

Array(%id = 18446745862042054398)


Now i want  to get a list  of  x-values in Array X ,  starting from  0  to N  :

example: array X =[x0= 0, x1=1/6, ...]

x[i]:= a+(b-a)*i/N; # for i = 0..N # endpoints subintervals

Error, invalid terms in product: 0 .. 30


# generate X-values for interval [a,b]

X:= Array(0..N, [seq(j, j=a..b, x[i])]);

Error, invalid input: seq expects its 3rd argument, step, to be of type numeric, but received x[i]



the values  x1,x2....stored  in Array X are used in further calulations
If there is a need for naming x1= 0 , x2= ..  in the Array A ? , probably not .





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