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These are questions asked by C_R

How to simplify this simple expression (...

C_R 3542 Maple
solve radical symbolic
October 30 2022
1 4

is a typical example of Maple output (in this case the natural frequency of a harmonic oscillator with m>0) where further simplification to text book notation is desired.

To get

the context menu did not help. On the command level, combine,radical (which I assumed is suitable) was also not effective.

Is there a better way to achieve the desired simplification than the one (found by trial and error) in the attachment?

If there is no better way: Would it make sense to improve the combine or any other command for such a case?

combining_radical.mw

How can I solve this units problem?...

C_R 3542 Maple 2022
units physics
October 22 2022
0 8

with(Physics)

diff(x(t), `$`(t, 2)) = a(t)

diff(diff(x(t), t), t) = a(t)

 (1)

dsolve(diff(diff(x(t), t), t) = a(t), arbitraryconstants = subscripted)

x(t) = Int(Int(a(t), t), t)+c__1*t+c__2

 (2)

a(t) = 1.*Unit('m'/'s'^2), c__1 = 2*Unit('m'/'s'), c__2 = 3*Unit('m')

a(t) = 1.*Units:-Unit(m/s^2), c__1 = 2*Units:-Unit(m/s), c__2 = 3*Units:-Unit(m)

 (3)

subs(a(t) = 1.*Units:-Unit(m/s^2), c__1 = 2*Units:-Unit(m/s), c__2 = 3*Units:-Unit(m), x(t) = Int(Int(a(t), t), t)+c__1*t+c__2)

x(t) = Int(Int(1.*Units:-Unit(m/s^2), t), t)+2*Units:-Unit(m/s)*t+3*Units:-Unit(m)

 (4)

value(%)

x(t) = (1/2)*t^2*Units:-Unit(m/s^2)+2*Units:-Unit(m/s)*t+3*Units:-Unit(m)

 (5)

NULL

Warning, units problem, not enough information to unambiguously deduce the units of the variables {t}; proceeding as if dimensionless

How can I provide the information to Maple that the unit of t is s?

 

Update: Temporarily disabling the warning would also be an option for the above case.

 

Download Unit_of_t.mw

CodeGeneration: How to force double?...

C_R 3542 Maple 2022
codegeneration
October 02 2022
1 5

I have started to use CodeGeneration[C] instead of codegen[C] (depreciated). In the attached example not all variables and parameters of a C function are declared as double, although the default value is double.

If this is by design:

How can I force double without going back to codegen[C] or manual declaration of each item?

C_code_generation_with_CodeGeneration.mw

How to extract symbols of the kind `tx` ...

C_R 3542 Maple
type indets name
September 21 2022
2 5

From an equation list originating from code optimization, a set of parameters and intermediate variables `tx` (where x is an integer) can be extracted.

{la, ra, rb, t, t10, t11, t12, t13, t15, t17, t18, t19, t21, t23, t24, t25, t26, t27, t28, t31, t32, t33, t34, t35, t36, t37, t39, t41, t42, t43, t44, t45, t46, t48, t49, t5, t50, t52, t53, t54, t55, t56, t57, t58, t59, t61, t62, t63, t64, t65, t67, t68, t69, t7, t70, t9, xa, za}

{la, ra, rb, t, t10, t11, t12, t13, t15, t17, t18, t19, t21, t23, t24, t25, t26, t27, t28, t31, t32, t33, t34, t35, t36, t37, t39, t41, t42, t43, t44, t45, t46, t48, t49, t5, t50, t52, t53, t54, t55, t56, t57, t58, t59, t61, t62, t63, t64, t65, t67, t68, t69, t7, t70, t9, xa, za}

 (1)

 

To extract from this list the intermediate variables for further processing I do

with(StringTools); intermediates := NULL; for i in {la, ra, rb, t, t10, t11, t12, t13, t15, t17, t18, t19, t21, t23, t24, t25, t26, t27, t28, t31, t32, t33, t34, t35, t36, t37, t39, t41, t42, t43, t44, t45, t46, t48, t49, t5, t50, t52, t53, t54, t55, t56, t57, t58, t59, t61, t62, t63, t64, t65, t67, t68, t69, t7, t70, t9, xa, za} do if `and`(is(FirstFromLeft(convert(i, string), t) = 1), type(parse(convert(i, string)[2]), integer)) then intermediates := intermediates, i end if end do

{intermediates}

{t10, t11, t12, t13, t15, t17, t18, t19, t21, t23, t24, t25, t26, t27, t28, t31, t32, t33, t34, t35, t36, t37, t39, t41, t42, t43, t44, t45, t46, t48, t49, t5, t50, t52, t53, t54, t55, t56, t57, t58, t59, t61, t62, t63, t64, t65, t67, t68, t69, t7, t70, t9}

 (2)

NULL

Quite some code for a little task. Can this be done more efficiently?

Download extract_tx.mw

Visual Studio Complier: Which version fo...

C_R 3542 MapleSim
compiler
September 08 2022
0 1

To make the "Simple External Code Function" example of the tutorial work, an external complier is required.

in MapleSim:-CreateDataRecord) invalid input: dsolve/numeric/ToExternal:-AddTempFile expects its 1st argument, f, to be of type string, but received [[["f1", 1864151924736]]] (3.597s)

Update:

help(Setup, Compiler) in Maple 2022 provides a link to supported compilers, which are Visual Studio 2017 and 2019.

In the list of available downloads there is no mention of "Express Edition". Which of the packages can be installed alternatively?

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