#### Assume a constant (3.2.00)

I would like to assume a parameter as a constant using MAPLE V R5 I used the following:

how can I assume a constant

##### Dr Francis J. Wright (4.2.00)

Here is one possible solution (in Maple V R5.1, but I think this has worked in most previous releases of Maple V):

##### Dr Francis J. Wright (4.2.00)

Here is one possible solution (in Maple V R5.1, but I think this has worked in most previous releases of Maple V):

##### Robert Israel (4.2.00)

There is a global variable ”constants” that contains all names that Maple knows as symbolic constants. To make L a constant, you just append it to this variable’s value:

If you want ”evalf” to give L a numerical value, you can assign that to evalf/constant/L. For example:

I get as result: 2. + L. As stated in the help page of evalf you should deﬁne evalf/constant/L as a procedure. If I do so: evalf/constant/L := proc() 1.2345 end: I get the above mentioned result for evalf(2+L). (U. Klein)

##### Colin Birch (7.2.00)

The error is that assume ﬁxes properties of variables and relationships between them. It cannot aﬀect types. The correct syntax for checking properties is:

> is(L,constant);

true

The confusion was caused because, as well as the property constant, there is also a type constant, which seems to include the type numeric and any names held within the global variable constants.

Thus it is possible to give a name or symbol the type constant, using a command like:

> constants := constants,myconstant;

I don’t know what the beneﬁt of doing this is.

There are other properties and types that share names, such as integer.

I hope this helps, but I am not sure what signiﬁcance the property constant has in Maple. Perhaps the question should be ”Why do you want to assume that L is constant?”