numerical issue resulting in negative hivpop -> inconsistent ART initiations

[jeffeaton]

This is not expected to happen in actual applications. Can't quite figure out what to do to address.

Small negative in Xartelig_15plus resulting in large ratio greater than 0 ratio for artelig_hm[hm] / Xartelig_15plus in line here:

eppasm/src/eppasm.cpp

Lines 913 to 914 in 30d4902

	( (1.0 - art_alloc_mxweight) * artelig_hm[hm] / Xartelig_15plus +
	art_alloc_mxweight * expect_mort_artelig_hm[hm] / expect_mort_artelig15plus);

Error occurs at t = 48, hts = 7, g = 0, ha = 0, hm = 6. Printed values of variables:

grad: -0.000000
artnum_hts: 27292.800000
artinit_hts: 21488.420514
artinit_hm: -213.749612
artelig: 2.081747e-16
Xartelig_15plus: -4.821249e-15
expect_mort_artelig15plus: 2.146363e-314

Issue discovered in Rob's ago-mort-disagg.pjnz example file when setting incidence rate to 0 (debugging discrepancy in ART coverage among entrants).

---

Example code:

pjnz <- "~/Downloads/ago-mort-disagg.pjnz"

fp <- prepare_directincid(pjnz)
fp$incidinput[] <- 0.0
fp$cd4_nonaids_excess_mort <- array(0.0, dim(fp$cd4_mort))
fp$art_nonaids_excess_mort <- array(0.0, dim(fp$art_mort))

modC <- simmod(fp)
modR <- simmod(fp, VERSION = "R")

round(colSums(attr(modC, "hivpop")[,,,49],,1) + colSums(attr(modC, "artpop")[,,,,49],,2),2)
round(apply(modC[,,2,49], 2, tapply, fp$ss$ag.idx, sum), 2)

round(colSums(attr(modR, "hivpop")[,,,49],,1) + colSums(attr(modR, "artpop")[,,,,49],,2),2)
round(apply(modR[,,2,49], 2, tapply, fp$ss$ag.idx, sum), 2)

Output:

> devtools::load_all()
ℹ Loading eppasm
> pjnz <- "~/Downloads/ago-mort-disagg.pjnz"
> fp <- prepare_directincid(pjnz)
> fp$incidinput[] <- 0.0
> fp$cd4_nonaids_excess_mort <- array(0.0, dim(fp$cd4_mort))
> fp$art_nonaids_excess_mort <- array(0.0, dim(fp$art_mort))
> modC <- simmod(fp)
modR <- simmod(fp, VERSION = "R")

> > round(colSums(attr(modC, "hivpop")[,,,49],,1) + colSums(attr(modC, "artpop")[,,,,49],,2),2)
         [,1]    [,2]
 [1,] 1278.34 1298.64
 [2,] 1492.60 1542.64
 [3,] 1710.75 1810.65
 [4,]  932.02 1048.01
 [5,]  305.96  349.94
 [6,] -101.56   55.19
 [7,]   -1.80    3.44
 [8,]    0.00    0.00
 [9,]    0.00    0.00
> round(apply(modC[,,2,49], 2, tapply, fp$ss$ag.idx, sum), 2)
     [,1]    [,2]
1 1278.34 1298.64
2 1492.60 1542.64
3 1710.75 1810.65
4  932.02 1048.01
5  305.96  349.94
6  -56.40   55.19
7   -0.36    3.44
8    0.00    0.00
9    0.00    0.00
> round(colSums(attr(modR, "hivpop")[,,,49],,1) + colSums(attr(modR, "artpop")[,,,,49],,2),2)
         [,1]    [,2]
 [1,] 1286.68 1298.64
 [2,] 1492.65 1542.64
 [3,] 1710.75 1810.65
 [4,]  945.62 1048.01
 [5,]  305.96  349.94
 [6,]   47.99   55.19
 [7,]    2.93    3.44
 [8,]    0.00    0.00
 [9,]    0.00    0.00
> round(apply(modR[,,2,49], 2, tapply, fp$ss$ag.idx, sum), 2)
     [,1]    [,2]
1 1286.68 1298.64
2 1492.65 1542.64
3 1710.75 1810.65
4  945.62 1048.01
5  305.96  349.94
6   47.99   55.19
7    2.93    3.44
8    0.00    0.00
9    0.00    0.00
>