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:
[1] LC_COLLATE=Italian_Italy.1252 LC_CTYPE=Italian_Italy.1252 LC_MONETARY=Italian_Italy.1252
[4] LC_NUMERIC=C LC_TIME=Italian_Italy.1252
attached base packages:
[1] stats graphics grDevices utils datasets methods base
other attached packages:
[1] lpSolveAPI_5.5.2.0-17.7
loaded via a namespace (and not attached):
[1] 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
[8] digest_0.6.27 rlang_0.4.7 evaluate_0.14