As an R user, I'm trying to read a CPLEX LP model from file by using the read.lp function from package lpSolveAPI. Here's the command line (from within RStudio):
lprec <- read.lp(filename="P01_a.lp",type = "lp")
I get this message:
Error in read.lp(filename = "P01_a.lp", type = "lp") : could not interpret P01_a.lp as an lp file.
Could you please help me? There seems to be no examples out there. I attach the LP file "P01_a.lp" in CPLEX format:
Minimize cost: 12q1 + 14q2 + 16q3 + 18q4 + 10r1 + 12r2 + 14r3 + 16r4 + 3s1 + 3s2 + 3s3 + 3s4 Subject To d1: q1 +r1 - s1 = 100 d2: s1 + q2 + r2 - s2 = 200 d3: s2 + q3 + r3 - s3 = 150 d4: s3 + q4 + r4 - s4 = 400 l1: q1 - 200b1 >= 0 l2: q2 - 200b2 >= 0 l3: q3 - 200b3 >= 0 l4: q4 - 200b4 >= 0 m1: r1 - 10000b1 <= 0 m2: r2 - 10000b2 <= 0 m3: r3 - 10000b3 <= 0 m4: r4 - 10000b4 <= 0 Bounds 0 <= q1 <= 200 0 <= q2 <= 200 0 <= q3 <= 200 0 <= q4 <= 200 Binary b1 b2 b3 b4 End
Here's my environment:
sessionInfo() R version 4.0.2 (2020-06-22) Platform: x86_64-w64-mingw32/x64 (64-bit) Running under: Windows 10 x64 (build 19041) Matrix products: default locale:  LC_COLLATE=Italian_Italy.1252 LC_CTYPE=Italian_Italy.1252 LC_MONETARY=Italian_Italy.1252  LC_NUMERIC=C LC_TIME=Italian_Italy.1252 attached base packages:  stats graphics grDevices utils datasets methods base other attached packages:  lpSolveAPI_220.127.116.11-17.7 loaded via a namespace (and not attached):  compiler_4.0.2 htmltools_0.5.0 tools_4.0.2 yaml_2.2.1 rmarkdown_2.3 knitr_1.29 xfun_0.16  digest_0.6.27 rlang_0.4.7 evaluate_0.14