From 7325e2460846ff3bf6836316b18582294a851562 Mon Sep 17 00:00:00 2001
From: Vincent van Hees <v.vanhees@accelting.com>
Date: Mon, 25 Mar 2024 17:25:07 +0100
Subject: [PATCH] increment time correctly between pages, fixes #61

---
 R/readGENEActiv.R       |  4 +++-
 inst/NEWS.Rd            |  1 +
 src/GENEActivReader.cpp | 12 +++---------
 3 files changed, 7 insertions(+), 10 deletions(-)

diff --git a/R/readGENEActiv.R b/R/readGENEActiv.R
index 6903dec..a3ececb 100644
--- a/R/readGENEActiv.R
+++ b/R/readGENEActiv.R
@@ -70,7 +70,9 @@ readGENEActiv = function(filename, start = 0, end = 0, progress_bar = FALSE,
   }
   
   # Correct timestamps
-  page_offset = (((start - 1) * 300) / rawdata$info$SampleRate)
+  if (start > 0) {
+    page_offset = (((start - 1) * 300) / rawdata$info$SampleRate)
+  }
   starttime_num = as.numeric(starttime_posix) + page_offset
   rawdata$time = rawdata$time + abs(rawdata$time[1]) + starttime_num
   return(invisible(list(
diff --git a/inst/NEWS.Rd b/inst/NEWS.Rd
index 0c89c3f..ca0fdb3 100755
--- a/inst/NEWS.Rd
+++ b/inst/NEWS.Rd
@@ -5,6 +5,7 @@
 \section{Changes in version 0.3.4 (release date:??-??-2024)}{
     \itemize{
       \item GENEActiv no longer prints error to console when more data is requested than is in the file because this is not an error, issue #58
+      \item readGENEActiv: Fixed bug in incrementing time between file pages #61
     }
 }
 
diff --git a/src/GENEActivReader.cpp b/src/GENEActivReader.cpp
index d02e737..8eea7f9 100644
--- a/src/GENEActivReader.cpp
+++ b/src/GENEActivReader.cpp
@@ -127,18 +127,14 @@ Rcpp::List GENEActivReader(std::string filename, std::size_t start = 0, std::siz
         while (std::getline(input_file, line)) {
             ++blockCount;
             if (blockCount >= start && blockCount <= end) {
+                blockTime = lastvalue;
                 // header: "Recorded Data" (0), serialCode (1), seq num (2),
                 // blockTime (3), unassigned (4), temp (5), batteryVolt (6),
                 // deviceStatus (7), freq (8), data (9)
                 for (int i = 1; i < blockHeaderSize; i++) {
                     try {
                         std::getline(input_file, header);
-                        if (i == 3) {
-                            std::stringstream ss(header);
-                            int milliseconds;
-                            ss >> milliseconds;
-                            blockTime = lastvalue + milliseconds;
-                        } else if (i == 5) {
+                        if (i == 5) {
                             std::stringstream ss(header);
                             ss.ignore(max_streamsize, ':');
                             ss >> temperature;
@@ -168,7 +164,6 @@ Rcpp::List GENEActivReader(std::string filename, std::size_t start = 0, std::siz
                 double y = 0.0;
                 double z = 0.0;
                 double t = 0.0;
-
                 int i = 0;
                 while (hexPosition < data.size() - 1) {
                     try {
@@ -182,9 +177,8 @@ Rcpp::List GENEActivReader(std::string filename, std::size_t start = 0, std::siz
                         x = (xRaw * 100. - mfrOffset[0]) / mfrGain[0];
                         y = (yRaw * 100. - mfrOffset[1]) / mfrGain[1];
                         z = (zRaw * 100. - mfrOffset[2]) / mfrGain[2];
-
                         t = (double)blockTime + (double)i * (1.0 / freq) * 1000;  // Unix millis
-                        lastvalue = t;
+                        lastvalue = t + (1.0 / freq) * 1000;
                         time_array.push_back(t);
                         x_array.push_back(x);
                         y_array.push_back(y);