Other Help

5.2.4 Other Help

1. A user may provide help and sometimes (rarely) get help for a user-defined function using the Help feature of the Define command.

Example

  Help();
Type Help(< Op >) to get help on operator < Op >
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  Help("GBasis");  -- note the typical response, one of the main
                 -- motivations for the author of the online manual.
No help available for GBasis
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2. The command, Describe , can be used to find more information about functions.

Example

  Describe Function("Insert");
Define Insert(L, I, O)
  $list.Insert(L, I, O)
EndDefine;
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  Describe Function("$list.Insert");
Define Insert(L, I, O)
  If NOT(Type(L) = LIST) Then
    Return(Error(ERR.BAD_PARAMS,": expected LIST"))
  ElsIf I = Len(L) + 1 Then
    Append(L, O)
  ElsIf I > Len(L) Then
    Return(Error(ERR.INDEX_TOO_BIG, I))
  ElsIf I <= 0 Then
    Return(Error(ERR.INDEX_NEG, I))
  Else
    L := Concat([L[J]|J In 1..(I - 1)],[O],[L[J]|J In I..Len(L)]);
  EndIf;
EndDefine;
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3. The function, Functions , may be used to list all functions defined in a package. Note: Functions("$user") lists all current user-defined functions.

Example

  Functions("$mat");
[About(), Man(), Identity(N), Transposed(M), Submat(M, Rows, Cols),
Jacobian(S), Resultant(F, G, X), DirectSum(M1, M2), BlockMatrix(LL),
ColumnVectors(M), Complement(M, I, J), Bip(M, J), Pfaffian(M),
Sylvester(F, G, X), ExtendRows(M, N), PushRows(M, N), ConcatRows(L),
PkgName()]
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The list of packages is given by Packages().

4. The function Starting(S) where S is a string returns a list of all functions starting with the string S.

Example

  Starting("Su");
["SubstPoly", "SubSet", "Submat", "Sum", "Subst", "Support"]
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