## 190 Reputation

14 years, 330 days

## Output in scientific notation...

Maple 15

Hi,

this question has been asked several times here already accoruding to the search function, but I didn't find an actual answer to it.

My Maple 15 gives outlarge numbers without scientific notation, so even 10^20 would be displayed as 1000....000  (20 zeroes). It seems like this is not the standard, so at one point I might have changed the way Maple displays the output, and cannot remember anymore how.

How can I tell Maple to display the output in scientiffic notation, and how can I set up the threshold of powers of ten, when this is done. (so that e.g. 100 still gets disaplyed as 100, and not as 1*10^2, but anything above gets displayed in scientific notation).

I know that I can right click on the output to change it's display form. But I want to change this generally, so I dont have to do this for any single numerical output I get.

I use Maple 15, running in Mac OS.

Thanks for help!

## When to use a Matrix, when an Array?...

Hi there!

Maple has lot's of datatypes which are very related to each other, such as Matrices and Arrays, or sets, lists and vectors.

Most of the time I am not quite sure which type is the "right" one to use for me, and I guess for most of the stuff I have done so far it didn't really matter. However now I am going a bit into numerics, and there things can get big and computationally expensive. Also, recently I got an error message stating that I would assign a large list to a variable, and should rather use an Array instead. So I guess I should start to bother what to use. : )

Obviously the Matrix has some advantages to the Array in the sense that I can perform matrix calculations with it easier using the LinearAlgebra package. So it can be transposed and what not. But is it disadvantegeous to the Array in any way, especially when it comes to large matrices in numerical calculations?

The same would interest me for sets, lists and Vectors.

Cheers!

Gernot

## procedures and datatypes of the argument...

Hi there!

I want to improve the way I code up my procedures. For instance I want to code them safe in the sense that they only accept the arguments when they have the correct type.

I know that in principle this is done with the double-colon operator in the following way:

proc(argument::argumenttype)::valuetype;

(Q1)Now, given that my argument is of a type such as set, list, Array, etc.:

(a) How would I specify the allowed types of the elements of that list (for all elements, and for specific ones)? And if the element of the list is a list again, how would I specify the type of that's elements? and so forth..

(b) How would I specify the allowed size of the listArray, etc. ?

(Q2) How do I specify the types of more than one output, if my proc returns more than one value?

(Q3) I know that there are special integer types, such as nonnegint, posint, negint. Is there also a way to specify that the ineger (or float) argument has to be greater than some given value, e.g. >2, or that it has to lie between two values, or out of a given set?

Thats all for now. Thanks for your help guys! : )

Gernot

## procedures: how do I assign an algebraic...

Maple

Hi there!

I want to have a procedure, which takes as one of it's arguments an algebraic, say sin(x) for instance. So far thats easy, I just type:

proc(arg)

Within this proc I would like to define a function now, which has this expression on it's image side. So it should look like . What I tried is:

minexample := proc(arg)

local f:

f := x -> arg:

f(pi)

end proc:

minexample(sin(x));

But this code would produce sin(x), as a result and not 0, as I would expect. Could anyone tell me what I do wrong, and how I can get it right please? : )

What I would also like to know is, what kind of data type expressions such as sin(x), or algebraic expressions are, so I can specify that in the definition already to make the proc more transparent to use.

Thanks!

## output cosmetics (collect, etc.)...

Maple

Hi there,

I got an output

and would like to bring it in the form

.

How do I do that? :)

In fact I don't even manage to collect the factor of 3*beta^2 as follows

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