I am trying to parse LTSpice data produced with a .step function. This splits the resulting dataset into parts which I do not know how to effectively handle using R.
library(tidyverse)
data <- read_tsv("FileName")
##
## ── Column specification ────────────────────────────────────────────────────────
## cols(
## time = col_character(),
## `V(out)` = col_double(),
## `V(in)` = col_double()
## )
## Warning: 24 parsing failures.
## row col expected actual file
## 1 -- 3 columns 1 columns 'FileName'
## 6 -- 3 columns 1 columns 'FileName'
## 11 -- 3 columns 1 columns 'FileName'
## 16 -- 3 columns 1 columns 'FileName'
## 21 -- 3 columns 1 columns 'FileName'
## ... ... ......... ......... ..............................
## See problems(...) for more details.
head(data)
## # A tibble: 6 x 3
## time `V(out)` `V(in)`
## <chr> <dbl> <dbl>
## 1 Step Information: Resistor1=10 Resistor2=1M Offset=-3 (Run… NA NA
## 2 0.000000000000000e+00 -1.50e-5 0
## 3 4.913626562387649e-09 3.08e-2 0.0309
## 4 4.996634374887648e-09 3.13e-2 0.0314
## 5 5.000000000000000e-09 3.14e-2 0.0314
## 6 Step Information: Resistor1=10.01K Resistor2=1M Offset=-3 … NA NA
As you can see, the data is split into parts, which are separated by information about the step. I would like to change the data so that the rows containing “Step Information” are deleted, and the corresponding parameters are written to a matching column:
## # A tibble: 6 x 6
## time `V(out)` `V(in)` Resistor1 Resistor2 Offset
## <chr> <dbl> <dbl> <lgl> <lgl> <lgl>
## 1 0.000000000000000e+00 -0.0000150 0 NA NA NA
## 2 4.913626562387649e-09 0.0308 0.0309 NA NA NA
## 3 4.996634374887648e-09 0.0313 0.0314 NA NA NA
## 4 5.000000000000000e-09 0.0314 0.0314 NA NA NA
## 5 0.000000000000000e+00 -0.00749 0 NA NA NA
## 6 4.908743749887649e-09 0.00789 0.0308 NA NA NA
EDIT:
Part of the raw data:
time V(out) V(in)
Step Information: Resistor1=10 Resistor2=1M Offset=-3 (Run: 1/24)
0.000000000000000e+00 -1.498494e-05 0.000000e+00
4.913626562387649e-09 3.082234e-02 3.086832e-02
4.996634374887648e-09 3.134312e-02 3.138962e-02
5.000000000000000e-09 3.136424e-02 3.141076e-02
Step Information: Resistor1=10.01K Resistor2=1M Offset=-3 (Run: 2/24)
0.000000000000000e+00 -7.485015e-03 0.000000e+00
4.908743749887649e-09 7.887614e-03 3.083766e-02
4.996634374887648e-09 8.162769e-03 3.138962e-02
5.000000000000000e-09 8.173305e-03 3.141076e-02
Step Information: Resistor1=20K Resistor2=1M Offset=-3 (Run: 3/24)
...
It's going to always be a bit ugly, but I reckon you're best served working with the raw data. Pull the lines in, flag the rows which have the Step information, separate the data out, then combine:
## read everything in as raw lines
## for this example use this code
## tmp <- readLines(textConnection(txt))
## for your real data use this code
tmp <- readLines("FileName")
## flag the Step Information rows
stl <- grepl("^Step", tmp)
## get all name=value pairs out of the Step Information rows and join together
nms <- regmatches(tmp[stl], gregexpr("\\S+(?=\\=)", tmp[stl], perl=TRUE))
val <- regmatches(tmp[stl], gregexpr("(?<=\\=)(\\S+)", tmp[stl], perl=TRUE))
nvp <- do.call(rbind, Map(function(v,n) as.data.frame(as.list(v), col.names=n), val, nms))
## finally put it all together
cbind(
read.table(text=tmp[!stl], header=TRUE),
nvp[ cumsum(stl)[!stl][-1], ]
)
# time V.out. V.in. Resistor1 Resistor2 Offset
#1 0.000000e+00 -1.498494e-05 0.00000000 10 1M -3
#1.1 4.913627e-09 3.082234e-02 0.03086832 10 1M -3
#1.2 4.996634e-09 3.134312e-02 0.03138962 10 1M -3
#1.3 5.000000e-09 3.136424e-02 0.03141076 10 1M -3
#2 0.000000e+00 -7.485015e-03 0.00000000 10.01K 1M -3
#2.1 4.908744e-09 7.887614e-03 0.03083766 10.01K 1M -3
#2.2 4.996634e-09 8.162769e-03 0.03138962 10.01K 1M -3
#2.3 5.000000e-09 8.173305e-03 0.03141076 10.01K 1M -3
The example data I used was:
txt <- "time\tV(out)\tV(in)
Step Information: Resistor1=10 Resistor2=1M Offset=-3 (Run: 1/24)
0.000000000000000e+00\t-1.498494e-05\t0.000000e+00
4.913626562387649e-09\t3.082234e-02\t3.086832e-02
4.996634374887648e-09\t3.134312e-02\t3.138962e-02
5.000000000000000e-09\t3.136424e-02\t3.141076e-02
Step Information: Resistor1=10.01K Resistor2=1M Offset=-3 (Run: 2/24)
0.000000000000000e+00\t-7.485015e-03\t0.000000e+00
4.908743749887649e-09\t7.887614e-03\t3.083766e-02
4.996634374887648e-09\t8.162769e-03\t3.138962e-02
5.000000000000000e-09\t8.173305e-03\t3.141076e-02"