C_R

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7 years, 13 days

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These are questions asked by C_R

After starting Maple

I then tried simpler prompts like "Hello", simplify(x),...

For all prompts I get the same error message.
I am not a frequent AI user but this is the first time I see that.
Has anybody else experienced the same?

Can someone send me a prompt that should work?

(Model type was Simple.)

Update:

It seems that this error occurs, when a second instance of Maple 2026.1 is started and AI is consulted in this instance. 

To D(ln@cosh) I have to add an argument to make it work (Edit: no output returned):

D(ln@cosh)(x);
                            sinh(x)
                            -------
                            cosh(x)

According to ?D I expected output according to this

I am only occasionally using Maple versions with the new ribon user interface and noticed about 2 weeks ago that I cannot interrupt for loops under these interfaces. For example this one

for i to 1000 do
    i^i;
end do

I re-run the code today (after installing windows updates) and could interrupt before the screen was filled with output but not after executing the code a second time (without restart).

Is that reproducible on other installations?

Are there other commands that cannot be interrupted? 
If that is known, are there workarounds?

Update:
I have restarted Maple and have two worksheets open with the same code. I can repeatedly interrupt in one worksheet but not in other

Given is a list of equations where the lhs is a name and the rhs an expression (i.e. list(name=algebraic).

I want to pass that list to a procedure and then assign locally the names to the values on the rhs. Similar to passing options in Maple commands (e.g. plot option numpoints=n).

The below, the example throws an error

restart;
foo := proc(params) 
local names; 
names := lhs~(params)[]; 
#local op(names);
print([names]):
assign(params); 
print(b, c, d); end proc;

foo([b = 2, c = 3, d = 4]);
foo([b = 2, c = 3, d = 4]); #  error because the assignement was done to global names

How to fix that and/or avoid assignements to global names

For a numericial integration I want to check if all physical parameters are given in SI base units (before stripping of the units for the integration). Right now I am doing this

restart

Parameters

H = 0.1e-1*Unit('m'), R = 0.6e-2*Unit('m'), r_sub = 0.3e-2*Unit('m'), k = .540*Unit('W'/('m'*'K')), rho = 1060.0*Unit('kg'/'m'^3), Cp = 3745*Unit('J'/('kg'*'K')), Q_flux = 5000*Unit('W'/'m'^2), T_amb = 0*Unit('K'), Nz = 20, Nr = 20, t_final = 30*Unit('s'), t_step = Unit('s'), test_1 = Unit('kW'), test_2 = 2*Unit('N')

H = 0.1e-1*Units:-Unit(m), R = 0.6e-2*Units:-Unit(m), r_sub = 0.3e-2*Units:-Unit(m), k = .540*Units:-Unit(W/(m*K)), rho = 1060.0*Units:-Unit(kg/m^3), Cp = 3745*Units:-Unit(J/(kg*K)), Q_flux = 5000*Units:-Unit(W/m^2), T_amb = 0, Nz = 20, Nr = 20, t_final = 30*Units:-Unit(s), t_step = Units:-Unit(s), test_1 = Units:-Unit(kW), test_2 = 2*Units:-Unit(N)

(1)

H: length of rod
R: outer radius
r_sub: outer radius of heat flux
k: conductance
ρ: density
Cp: heat capacity
Q_flux: heat flux
T_amb: initial Tempearture
Nz: number of axial grid points
Nr: number of radial grid points
t_final: integration time
t_step: sampling interval for temperature fields
test_1: unit given in kilos
test_2: unit given in derived base units

alpha = k/(rho*Cp); simplify(subs(H = 0.1e-1*Units:-Unit(m), R = 0.6e-2*Units:-Unit(m), r_sub = 0.3e-2*Units:-Unit(m), k = .540*Units:-Unit(W/(m*K)), rho = 1060.0*Units:-Unit(kg/m^3), Cp = 3745*Units:-Unit(J/(kg*K)), Q_flux = 5000*Units:-Unit(W/m^2), T_amb = 0, Nz = 20, Nr = 20, t_final = 30*Units:-Unit(s), t_step = Units:-Unit(s), test_1 = Units:-Unit(kW), test_2 = 2*Units:-Unit(N), %))

alpha = 0.1360304305e-6*Units:-Unit(m^2/s)

(2)

α: thermal diffusivity

 

One way is to check whether the value of a physical parameter has not changed after simplification

`minus`(map(convert, simplify(`~`[rhs]({Cp = 3745*Units:-Unit(J/(kg*K)), H = 0.1e-1*Units:-Unit(m), Nr = 20, Nz = 20, Q_flux = 5000*Units:-Unit(W/m^2), R = 0.6e-2*Units:-Unit(m), T_amb = 0, k = .540*Units:-Unit(W/(m*K)), r_sub = 0.3e-2*Units:-Unit(m), rho = 1060.0*Units:-Unit(kg/m^3), t_final = 30*Units:-Unit(s), t_step = Units:-Unit(s), test_1 = Units:-Unit(kW), test_2 = 2*Units:-Unit(N)})), unit_free), map(convert, `~`[rhs]({Cp = 3745*Units:-Unit(J/(kg*K)), H = 0.1e-1*Units:-Unit(m), Nr = 20, Nz = 20, Q_flux = 5000*Units:-Unit(W/m^2), R = 0.6e-2*Units:-Unit(m), T_amb = 0, k = .540*Units:-Unit(W/(m*K)), r_sub = 0.3e-2*Units:-Unit(m), rho = 1060.0*Units:-Unit(kg/m^3), t_final = 30*Units:-Unit(s), t_step = Units:-Unit(s), test_1 = Units:-Unit(kW), test_2 = 2*Units:-Unit(N)}), unit_free))

{1000}

(3)

if is(`minus`(map(convert, simplify(`~`[rhs]({Cp = 3745*Units:-Unit(J/(kg*K)), H = 0.1e-1*Units:-Unit(m), Nr = 20, Nz = 20, Q_flux = 5000*Units:-Unit(W/m^2), R = 0.6e-2*Units:-Unit(m), T_amb = 0, k = .540*Units:-Unit(W/(m*K)), r_sub = 0.3e-2*Units:-Unit(m), rho = 1060.0*Units:-Unit(kg/m^3), t_final = 30*Units:-Unit(s), t_step = Units:-Unit(s), test_1 = Units:-Unit(kW), test_2 = 2*Units:-Unit(N)})), unit_free), map(convert, `~`[rhs]({Cp = 3745*Units:-Unit(J/(kg*K)), H = 0.1e-1*Units:-Unit(m), Nr = 20, Nz = 20, Q_flux = 5000*Units:-Unit(W/m^2), R = 0.6e-2*Units:-Unit(m), T_amb = 0, k = .540*Units:-Unit(W/(m*K)), r_sub = 0.3e-2*Units:-Unit(m), rho = 1060.0*Units:-Unit(kg/m^3), t_final = 30*Units:-Unit(s), t_step = Units:-Unit(s), test_1 = Units:-Unit(kW), test_2 = 2*Units:-Unit(N)}), unit_free)) <> {}) then print("Not all units are in SI base units") end if

"Not all units are in SI base units"

(4)

Download check_for_SI_base_units.mw

I am interested in simpler ways to perform the test. The statement is quite long and not easy to understand.

Given the size of the unit package, there might be a command that I have overlooked to check whether units are in SI base units.

Have I missed test cases to make the check fool proof?

 

Update: A variant with split was added and attempts with functional programming

check_for_SI_base_units_02.mw

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