This is version 2. Clearer description. Ignore the earlier one.
Thanks in advance. All insight is appreciated. R is great!
HELP NEEDED DESCRIPTION
==============================
A. Matching the "lappt" to the spatial polygon. To correctly retrieve
the Slot "labpt" to use
in method ptp(). Slot "labpt" and measurements are all in WSG84 long
lat (see below).
Slot "labpt":
[1] -96.75983 32.93319
Working from the example found below. There might be a better way.
http://nceas.ucsb.edu/scicomp/GISSeminar/UseCases/PointInPolygonAnalysis/point_in_poly.html
B. Iteration through all polygons in each of the two spatial polygon
data frames.
POLYGON DESCRIPTION, ITERATION, OUTPUT
==============================
1. blk_sp contains many spatial polygons that fit entirely
into different pct_big_sp spatial polygons. No
overlapping exists.
Yes these are US census blocks
2. pct_big_sp contains around thirty different blk_sp
spatial polygons.
Yes these are precincts that contain the census blocks.
3. How this might work.
a. iterate through every pct_big_sp, then blk_sp
b. compares the blk_sp Slot "labpt" (lat long format) to the
outside edge of the larger polygon b_big_sp. Probably
with pip().
c. output the matching blk_sp IDs into an match_df data
frame. On a match, gather the following items as we
iterate.
. blk_sp's ID name BLK
. pct_big_sp's ID name PCT
d. c_df output data frame example.
BLK PCT
"480019510006079",1811
"480019510006080",1811
"480019510006998",1811
"480019510006999",1811
"480039501003000",1120
"480039501003001",1120
"480039501003002",1120
"480039501003003",1120
Thanks,
Jim Burke
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