Fix #28 (#29)

* fix #28

* rm extra space

* bump batch

Project.toml

@@ -1,7 +1,7 @@
 name = "TimeSpans"
 uuid = "bb34ddd2-327f-4c4a-bfb0-c98fc494ece1"
 authors = ["Beacon Biosignals, Inc."]
-version = "0.2.6"
+version = "0.2.7"
 
 [deps]
 Dates = "ade2ca70-3891-5945-98fb-dc099432e06a"

src/TimeSpans.jl

@@ -208,11 +208,15 @@ julia> index_from_time(100, Millisecond(1000))
 101
 ```
 """
-function index_from_time(sample_rate, sample_time::Period)
+index_from_time(sample_rate, sample_time::Period) = first(index_and_is_rounded_from_time(sample_rate, sample_time))
+
+# Helper to get the index and whether or not it has been rounded
+function index_and_is_rounded_from_time(sample_rate, sample_time::Period)
     time_in_nanoseconds = convert(Nanosecond, sample_time).value
     time_in_nanoseconds >= 0 || throw(ArgumentError("`sample_time` must be >= 0 nanoseconds"))
     time_in_seconds = time_in_nanoseconds / NS_IN_SEC
-    return floor(Int, time_in_seconds * sample_rate) + 1
+    index = time_in_seconds * sample_rate + 1
+    return floor(Int, index), !isinteger(index)
 end
 
 """
@@ -233,8 +237,12 @@ julia> index_from_time(100, TimeSpan(Second(3), Second(6)))
 """
 function index_from_time(sample_rate, span)
     i = index_from_time(sample_rate, start(span))
-    j = index_from_time(sample_rate, stop(span))
-    j = i == j ? j : (j - 1)
+    j, is_rounded = index_and_is_rounded_from_time(sample_rate, stop(span))
+    # if `j` has been rounded down, then we are already excluding the right endpoint
+    # by means of that rounding. Hence, we don't need to decrement here.
+    if i != j && !is_rounded
+        j -= 1
+    end
     return i:j
 end
 

test/runtests.jl

@@ -81,6 +81,12 @@ end
     @test index_from_time(100, Nanosecond(0)) == 1
     @test index_from_time(100, TimeSpan(Second(3), Second(6))) == 301:600
     @test index_from_time(100, TimeSpan(Second(1))) == 101:101
+
+    # https://github.com/beacon-biosignals/TimeSpans.jl/issues/28
+    @test index_from_time(1, Millisecond(1500)) == 2
+    @test index_from_time(1, Millisecond(2500)) == 3
+    @test index_from_time(1, TimeSpan(Millisecond(1500), Millisecond(2500))) == 2:3
+
     # test non-integer sample rates
     rate = 100.66
     ns_per_sample = nanoseconds_per_sample(rate)