4.3.1.1 Data types

AMI supports a set of different datatypes and it can handle these types within all defined functions.

• constants: any number within AMI is interpreted as a constant value with the precision of a C-double value
• variables: any non numeric value within AMI is interpreted as a variable which can represent any datatype.

  <varname> = <any AMI datatype>
  

• running variables: are defined as a set of integer values
  i = x, i = x + 1, i = x + 2,..., i = x + n = y

   i = x .. y     # running variable from value x to y
  

• vectors: represent a one-dimensional field including constants and variables. If vectors include variables representing vectors or matrices the dimension is automatically expanded to fit the new datatype.

  [<a1>,<a2>,...,<an>]             # row vector 
  [[<a1>][<a2>][...][<an>]]        # column vector
  

• matrices: represent an n-dimensional field including constants and variables. If matrices include variables representing vectors or matrices the dimensions are automatically expanded to fit the new datatype.

  [[<a11>,<a12>,...,<a1n>]         # matrix definition
   [<a21>,<a22>,...,<a2n>]         # within AMI
   [       ...           ]
   [<am1>,<am2>,...,<amn>]]
  

  A single value of a vector or matrix can be accessed using the index written style supported by the model description language of AMI, shown in the following examples.

  # EXAMPLE 1:
  var1 = A[1];           # variable var1 represents the first
                         # value of the vector A
  
  # EXAMPLE 2:
  i = 1..5;
  var2[i] = A[i+1];      # variable var2 is a vector of size 1x5
                         # with the values of vector A[2] to A[6];
  
  # EXAMPLE 3:
  i = 1..5;
  f(x,y) = x+y;
  
  var3[i] = f(A[i],B[i+1]); 
                         # variable var3 is a vector of size 1x5
                         # with the sum of A[1]+B[2] to A[5]+B[6];
  
  #EXAMPLE 4:
  var4 = (A.t0 - A.t1)/(t.t0 - t.t1)
                         # variable var4 is a vector of size 1x6
                         # holding the discretized first order
                         # derivatives in time for quantity A