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How to solve this equation in symbolic form so that the resulting solution can be used as a formula in Excel?

Is it possible?

C = constant

with(Units[Standard]);
A := 2*Unit('Pa');
x := 0;
sqrt(A^2);

In this example defining the 'x' variable returns an error message: "Error, (in simplify/sqrt/fraction) invalid input: denom expects its 1st argument, x, to be of type {algebraic, list, set}, but received pascal".

You can use any Unit in 'A' variable.

Using a Cyrillic font in the Combo Box component gives an runtime error when saving workbook file (*.maple file extension).

cyr_wb_save_error.zip

Select the second item in Combo Box component and press save button.

 

Hello!

Using a geometry package, I ran into a problem: the area() function returns the wrong value for square elements.

What am I doing wrong?

_local(D)

with(geometry)

b := 2

h := 1

square(sq1, [point(A, 0, 0), point(B, b, 0), point(C, b, h), point(D, 0, h)])

evalf(area(sq1))

2.500000000

(1)

draw([sq1, A(printtext = true), B(printtext = true), C(printtext = true), D(printtext = true)])

 

triangle(tr1, [point(A, 0, 0), point(B, b, 0), point(C, b, h)])

evalf(area(tr1))

1.

(2)

draw([tr1, A(printtext = true), B(printtext = true), C(printtext = true)])

 

NULLNULL

NULL

b := .1

h := 1

square(sq2, [point(A, 0, 0), point(B, b, 0), point(C, b, h), point(D, 0, h)])

evalf(area(sq2))

.5050000000

(3)

draw([sq2, A(printtext = true), B(printtext = true), C(printtext = true), D(printtext = true)])

 

triangle(tr2, [point(A, 0, 0), point(B, b, 0), point(C, b, h)])

evalf(area(tr2))

0.5000000000e-1

(4)

draw([tr2, A(printtext = true), B(printtext = true), C(printtext = true)])

 

``


 

Download GeometryAreaTest.mw

I have a problem using variables values that were read form Maple library file (*.mla) with units.

For example:

In the first file called "calculations.mw" I calculate a variable with units and save value to "lib1.mla" file

 

A__1 := Units:-Standard:-`*`(2, Unit('m'))

2*Units:-Unit('m')

(1)

A1 := Units:-Standard:-Unit('m')

Units:-Unit('m')

(2)

savelib('A__1', 'A1', cat(interface(worksheetdir), "\\lib1.mla"))

``

 

 

Download calculations.mw

 

 

In the second file called "document.mw" I can read the value of a variable, but can't use it in expressions:

 

libname := cat(interface(worksheetdir))

"D:\TEMP\MTest"

(1)

A__1

2*Units:-Unit('m')

(2)

A__1

2*Units:-Unit('m')

(3)

2*A__1

Error, (in Units:-Standard:-*) invalid subscript selector

 

A1

Units:-Unit('m')

(4)

A1

Units:-Unit('m')

(5)

2*A1

Error, (in Units:-Standard:-*) invalid subscript selector

 

NULL

 

Download document.mw

 

Where I made a mistake? 

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