BUILDARR

Name

buildarr

Purpose (one Line Only)

Build up a master array by concatenation

Description

This routine does very little, really. It just allows you to
concatenate vectors, one at a time while also handling the
first time when the output array doesn't yet exist. This was
written to help clean up a common code construct that would look
this this:
nval=0
for i=0,nother do begin
generate some vectors, say a,b,c
if nval eq 0 then begin
aa=a
bb=b
cc=c
endif else begin
aa=[aa,a]
bb=[bb,b]
cc=[cc,c]
endelse
nval += n_elements(a) ; assuming a,b,c same length
endfor
With this routine this same action looks like:
nval=0
for i=0,nother do begin
generate some vectors, say a,b,c
buildarr,aa,a,nval eq 0
buildarr,bb,b,nval eq 0
buildarr,cc,c,nval eq 0
nval += n_elements(a) ; assuming a,b,c same length
endfor

Calling Sequence

buildarr,array,newarray,nval

Inputs

array - The is the master array that is to be built. On input it
will either be empty or contain values already placed in
the array.
newarray - Value or values to add to the master array.
nval - Number of valid values already in the master array. All that
really matters here is that nval be set to zero on the first
time adding to the array and after that it's not zero.

Optional Input Parameters

Keyword Input Parameters

Outputs

array - Is modified by adding new array to end.

Keyword Output Parameters

Common Blocks

Side Effects

Restrictions

Procedure

Modification History

2010/03/02, Written by Marc W. Buie, Southwest Research Institute