ttt_flowmapper_types: ttt_flowmapper_types: Compute gross and net flows

In tributetotobler/ttt: Tribute to Tobler

ttt_flowmapper_types: Compute gross and net flows

Description

Compute gross (symmetric) and net (antisymetric) flows from initial asymetric matrix

Usage

ttt_flowmapper_types(
  tab,
  origin = NULL,
  destination = NULL,
  fij = NULL,
  format,
  type,
  lowup,
  net
)

Arguments

tab	is the input flow dataset
origin	the place of origin code
destination	the place of destination code
fij	the flow value between origin and destination places
format	specify the flow dataset format, "M " for square matrix or "L" for long [i,j,data]
type	enter the flowtype : "gross" or "net". See Details.
lowup	for extracting the lower or upper triangular sub-portion of the gross matrix. See Details.
net	for extracting the "positive" or the "negative" flow values of the net matrix

Details

Type of flow are:
- type = "gross" for building the gross matrix - as bilateral volum
- type = "net" for building the net matrix - as bilateral balance
Lowup part of the matrix are:
- lowup ="up" for triangular part above the main diagonal
- lowup = "low" for triangular part below the main diagonal

References

Waldo R. Tobler, 1979, A geographical flow mapping program, Geographical Analysis, n°13, Vol. 1, pp. 1-20

Examples

#Example 1 : building gross flows
gross_up<-ttt_flowmapper_types(data, origin="i",destination="j",fij="fij", format="L", type="gross",lowup="up")

#Example 2 : building net flows
net_positive <-ttt_flowmapper_types(data,origin="i",destination="j",fij="fij",format="L",type="net",net="positive")
 

tributetotobler/ttt documentation built on Sept. 15, 2022, 5:41 p.m.