General Form:

let name = expr

Creates a new vector called name with the value specified by expr, an expression as described above. If expr is [] (a zero-length vector) then the vector becomes undefined. Individual elements of a vector may be modified by appending a subscript to name (ex. name[0]). If there are no arguments, let is the same as display.

The command let creates a vector in the current plot. Use setplot (17.5.65) to create a new plot.

There is no straightforward way to initialize a new vector. In general, one might want let initialize a slice (i.e. name[4:4,21:23] = [ 1 2 3 ]) of a multi-dimensional matrix of arbitrary type (i.e. real, complex ..), where all values and indexes are arbitrary expressions. This will fail. The procedure is to first allocate a real vector of the appropriate size with either vector(), unitvec(), or [ n1 n2 n3 ... ]. The second step is to optionally change the type of the new vector (to complex) with the j() function. The third step reshapes the dimensions, and the final step (re)initializes the contents, like so:

let a = j(vector(10))

reshape a [2][5]

let a[0][0] = (pi,pi)

Initialization of real vectors can be done quite efficiently with compose:

compose a values (pi, pi) (1,1) (2,sqrt(7)) (boltz,e)

reshape a [2][2]

See also unlet (17.5.88), compose (17.5.13).